Greek Science - History

Greek Science - History


We are searching data for your request:

Forums and discussions:
Manuals and reference books:
Data from registers:
Wait the end of the search in all databases.
Upon completion, a link will appear to access the found materials.


The Greeks, led by Aristotle, developed the principles of scientific investigation: empirical research -- systematic observation -- as the basis for generalization.

The most famous scientist of the period was Archimedes. Archimedes developed important aspects of the mathematics of geometry. Archimedes also designed many important inventions.


Greek Science - History

A Brief History of Science

Humankind has always been inquisitive, needing to understand why things behave in a certain way, and trying to link observation with prediction. For example, since prehistoric times we have observed the heavens and tried to make sense of the seasonal changes in the position of the sun, moon and stars. In about 4000 BC, the Mesopotamians tried to explain their observations by suggesting that the Earth was at the center of the Universe, and that the other heavenly bodies moved around it. Humans have always been interested in the nature and origins of this Universe.

But they weren't only interested in astronomy. The extraction of iron, which led to the Iron Age, is a chemical process which early metallurgists developed without understanding any of the science involved. Nevertheless, they were still able to optimise the extraction by trial and error. Before this, copper and tin were extracted (which led to the Bronze Age) and later, zinc. Exactly how each of these processes was discovered is lost in the mists of time, but it is likely that they were developed using observation and experiment in a similar way to that used by today's scientists.

Early humankind also observed that certain plants could be used to treat sickness and disease, and herbal medicines were developed, some of which are still used by modern pharmaceutical companies to provide leads for new synthetic drugs.

The first people to try and develop the theory behind their observations were the Greeks: people such as Pythagoras, who concentrated on a mathematical view of the world. Similarly, Aristotle and Plato developed logical methods for examining the world around them. It was the Greeks who first suggested that matter was made up of atoms — fundamental particles that could not be broken down further.

But it wasn't only the Greeks who moved science on. Science was also being developed in India, China, the Middle East and South America. Despite having their own cultural view of the world, they each independently developed materials such as gunpowder, soap and paper. However, it wasn't until the 13th century that much of this scientific work was brought together in European universities, and that it started to look more like science as we know it today. Progress was relatively slow at first. For example, it took until the 16th century for Copernicus to revolutionise (literally) the way that we look at the Universe, and for Harvey to put forward his ideas on how blood circulated round the human body. This slow progress was sometimes the result of religious dogma, but it was also a product of troubled times!

The Birth of Modern Science

It was in the 17th century that modern science was really born, and the world began to be examined more closely, using instruments such as the telescope, microscope, clock and barometer. It was also at this time that scientific laws started to be put forward for such phenomena as gravity and the way that the volume, pressure and temperature of a gas are related. In the 18th century much of basic biology and chemistry was developed as part of the Age of Enlightenment.

The 19th century saw some of the great names of science: people like the chemist John Dalton, who developed the atomic theory of matter, Michael Faraday and James Maxwell who both put forward theories concerning electricity and magnetism, and Charles Darwin, who proposed the (still) controversial theory of evolution. Each of these developments forced scientists radically to re-examine their views of the way in which the world worked.

The last century brought discoveries such as relativity and quantum mechanics, which, again, required scientists to look at things in a completely different way. It makes you wonder what the iconoclastic discoveries of this century will be.

The table below sets out the time-scale of some of the major events in Earth history and developments in science and technology. It shows something of the parallel development of human communication and of science and its technological applications, set in the context of Earth history as a whole. The years before present (BP) shown in this table are, of course, approximate, in that they merely imply 'about that long ago'. As far as the older times are concerned, clearly no scientist could prove that the Earth was formed exactly 4,600,000,000 years ago, or that the first human settlements were established 12,000 years ago.

Years BP Events in Earth History
4 600 000 000 Earth and planets in the solar system formed
3 800 000 000 first evidence of life
440 000 000 evolution of first land plants
400 000 000 evolution of first land animals
3 000 000 evolution of first hominids (human-like creatures)
Developments in science and technology Developments in communication
35 000 fluent human speech
12 000 first human settlements
9 000 use of stone tools
6 000 first primitive writing based on pictures (Egypt and Mesopotamia)
5 800 first use of bronze (alloy of tin and copper)
3 700 first alphabet developed (Palestine)
3 500 first use of iron
2 600 era of Greek science, based on philosophy (Aristotle, Pythagoras)
1 000 Chinese invented printing
700 experimental science of William of Occam
500 Earth orbits the Sun (Copernicus) first printing press (Caxton)
400 circulation of blood (Harvey)
300 theory of gravity (Newton) invention of telescope
200 Industrial Revolution (in Britain)
150 Theory of evolution by natural selection (Darwin) early railways photography invented
100 first powered flight theory of special relativity (Einstein) wireless telegraphy invented
50-60 first fully-electronic computer
40-50 structure of DNA (Watson and Crick) first human in Earth orbit (Gagarin)
30-40 first human on the moon (Armstrong) computers with silicon chips
0-20 Human Genome Mapping Project multiple organ transplants lap-top computers communications networking the Internet artificial intelligence

Major funding for Rough Science was provided by the National Science Foundation. Corporate funding was provided by Subaru.


Ancient Greek and Roman Science

Ancient Greek and Roman science – when we speak about them we normally use the word ‘science’, even though some people would complain that it’s a bit anachronistic that we are using a term that isn’t really appropriate for the period, but it’s probably the best one we have, because when we use the word ‘science’, I think that we’re referring to our attempts to explain and understand the natural world. I would distinguish science from technology. I think that technology is talking about our attempts to control the natural world. I think an interesting example that it’s sometimes difficult to know whether it’s science or technology in ancient Greece is that of medicine, because we know that some of the ancient Greek physicians were very interested in understanding health and disease, not only in controlling it. When I talk about ancient Greek and Roman science, I’m talking about attempts to explain and understand the natural world, which would include what things are made of, how the world began – if it did begin – or how it has always been here, animals – are they different from humans, and what characteristics they might share, to understand plants all different aspects of the natural world.

The modern English word ‘science’ is related to the Latin word ‘scientia’, the ancient Greek word for knowledge was ‘episteme’. Probably neither word is exactly carrying the meaning of our modern word ‘science’, and we use the word ‘science as a shorthand of referring to attempts to explain and understand nature. The word ‘technology’ has a rather different meaning – I think that it refers to our attempts to control nature, rather than understand it. Sometimes we can control it or attempt to control it without understanding, sometimes we can understand nature, but not control it.

How do we know what the ancient Greeks and Romans thought about the natural world?

One of our best ways of accessing their ideas are through the writings that they left. But we are also fortunate to have some artifacts that survive, and also descriptions of artifacts. We know for instance that there were scientific instruments, for example, astronomical instruments that were devised and used. Hundreds of sundials actually survive from ancient Greece and Rome. We know also from their records that they made many observations of the natural world we also have accounts of various sorts of experiments that were carried out. Aristotle is one of the ancient philosophers who tells us about the experiments that he ran.

I think one of the challenges for understanding and studying the science of the ancient Greek and Roman world is to have a very wide view of what it is that we are meant to be studying. I think that we have in the past tended to focus on the great names of ancient science – much as we focused on the great names of more modern science – and we focused for instance on the works of Aristotle, Galen, Ptolemy, and sometimes we’ve neglected works that may seem to be of lesser importance. But just as today science is not only done by people who are going to win a Nobel prize, so too in antiquity – it wasn’t only the great figures like Archimedes, who did maths, but also many anonymous people whose names we don’t know but who seem to have been responsible for some of the ancient mathematical problems that actually survive. We also have texts whose author we don’t know – I think of a poem that’s referred to as the Etna poem, that talks about the volcano Etna. We don’t know wrote it. It’s a work that’s very interesting and tells us a good deal about at least one person’s theories and ideas about volcanoes. Even though we don’t know who wrote it it’s still well worth studying. One of our challenges, therefore, is to really open our eyes and embrace that there is a much wider range of technical and scientific literature out there that we haven’t yet explored. And of course, we are always hoping that we are going to discover another text – that sometimes happens – or discover a new artifact and that there will be something completely new to give us a new window onto the ancient Greek and Roman science.

Our access to ancient knowledge about the natural world is primarily but not only through the written texts. It’s very interesting that there are some very important texts. I think for instance of Plato’s Timaeus that talks about the creation of the world and talks about the mathematical structure of the world – some of it is couched in what might be regarded as somewhat mythological terms and yet it is a very technical text, and certainly it was very important historically in terms of informing later scientific and mathematical conceptions of the world. This is a text that, very surprisingly, is not often read. There are other works by Aristotle – I think for instance of his meteorology, that’s a work that very few people who work on Aristotle’s philosophy have actually read. So I think that there is quite a bit of material out there that we need to explore and we need to engage with more closely. So I think that as in many other fields of study we tend to go down certain paths that have already been well-trodden and I think that we need to branch out and read more texts.


Contents

Practical knowledge Edit

The practical concerns of the ancient Greeks to establish a calendar is first exemplified by the Works and Days of the Greek poet Hesiod, who lived around 700 BC. The Works and Days incorporated a calendar, in which the farmer was to regulate seasonal activities by the seasonal appearances and disappearances of the stars, as well as by the phases of the Moon which were held to be propitious or ominous. [1] Around 450 BC we begin to see compilations of the seasonal appearances and disappearances of the stars in texts known as parapegmata, which were used to regulate the civil calendars of the Greek city-states on the basis of astronomical observations. [2]

Medicine provides another example of practically oriented investigation of nature among the Ancient Greeks. It has been pointed out that Greek medicine was not the province of a single trained profession and there was no accepted method of qualification of licensing. Physicians in the Hippocratic tradition, temple healers associated with the cult of Asclepius, herb collectors, drug sellers, midwives, and gymnastic trainers all claimed to be qualified as healers in specific contexts and competed actively for patients. [3] This rivalry among these competing traditions contributed to an active public debate about the causes and proper treatment of disease, and about the general methodological approaches of their rivals. In the Hippocratic text, On the Sacred Disease, which deals with the nature of epilepsy, the author attacks his rivals (temple healers) for their ignorance and for their love of gain. The author of this text seems modern and progressive when he insists that epilepsy has a natural cause, yet when he comes to explain what that cause is and what the proper treatment would be, his explanation is as short on specific evidence and his treatment as vague as that of his rivals. [4]

There were several acute observers of natural phenomena, especially Aristotle and Theophrastus, who wrote extensively on animals and plants. Theophrastus also produced the first systematic attempt to classify minerals and rocks, summarised in the Naturalis Historia of Pliny the Elder in 77 AD.

Pre-Socratic philosophers Edit

Materialist philosophers Edit

The earliest Greek philosophers, known as the pre-Socratics, were materialists who provided alternative answers to the same question found in the myths of their neighbors: "How did the ordered cosmos in which we live come to be?" [7] But although the question is much the same, their answers and their attitude towards the answers is markedly different. As reported by such later writers as Aristotle, their explanations tended to center on the material source of things.

Thales of Miletus (624–546 BC) considered that all things came to be from and find their sustenance in water. Anaximander (610–546 BC) then suggested that things could not come from a specific substance like water, but rather from something he called the "boundless." Exactly what he meant is uncertain but it has been suggested that it was boundless in its quantity, so that creation would not fail in its qualities, so that it would not be overpowered by its contrary in time, as it has no beginning or end and in space, as it encompasses all things. [8] Anaximenes (585–525 BC) returned to a concrete material substance, air, which could be altered by rarefaction and condensation. He adduced common observations (the wine stealer) to demonstrate that air was a substance and a simple experiment (breathing on one's hand) to show that it could be altered by rarefaction and condensation. [9]

Heraclitus of Ephesus (about 535–475 BC), then maintained that change, rather than any substance was fundamental, although the element fire seemed to play a central role in this process. [10] Finally, Empedocles of Acragas (490–430 BC), seems to have combined the views of his predecessors, asserting that there are four elements (Earth, Water, Air and Fire) which produce change by mixing and separating under the influence of two opposing "forces" that he called Love and Strife. [11]

All these theories imply that matter is a continuous substance. Two Greek philosophers, Leucippus (first half of the 5th century BC) and Democritus of Abdera (lived about 410 BC) came up with the notion that there were two real entities: atoms, which were small indivisible particles of matter, and the void, which was the empty space in which matter was located. [12] Although all the explanations from Thales to Democritus involve matter, what is more important is the fact that these rival explanations suggest an ongoing process of debate in which alternate theories were put forth and criticized.

Xenophanes of Colophon prefigured paleontology and geology as he thought that periodically the earth and sea mix and turn all to mud, citing several fossils of sea creatures that he had seen. [13]

Pythagoreans Edit

The materialist explanations of the origins of the cosmos seems to miss an important point. It doesn't make much sense to think that an ordered universe comes out of a random collection of matter. How can a random assemblage of fire or water produce an ordered universe without the existence of some ordering principle?

The first step in this emphasis upon a model was that of the followers of Pythagoras (approximately 582 – 507 BC), who saw number as the fundamental unchanging entity underlying all the structure of the universe. For Pythagoras and his followers matter was made up of ordered arrangements of point/atoms, arranged according to geometrical principles into triangles, squares, rectangles, and so on. Even on a larger scale, the parts of the universe were arranged on the principles of a musical scale and a number. For example, the Pythagoreans held that there were ten heavenly bodies because ten is a perfect number, the sum of 1 + 2 + 3 + 4. Thus with the Pythagoreans we find number emerging as the rational basis for an orderly universe — as the first proposal for a scientific ordering principle of the cosmos. [14]

Plato and Aristotle Edit

Like the Pythagoreans, Plato (c. 427–c. 347 BC) found the ordering principle of the universe in mathematics, specifically in geometry. A later account has it that Plato had inscribed at the entrance to his school, the Academy, "Let no man ignorant of geometry enter." [15] The story is a myth, but it has a grain of truth, for in his writings Plato repeatedly tells us of the importance of geometry.

Plato is known more for his contributions to the philosophical basis of scientific method than to particular scientific concepts. He maintained that all things in the material world are imperfect reflections of eternal unchanging ideas, just as all mathematical diagrams are reflections of eternal unchanging mathematical truths. Since Plato believed that material things had an inferior kind of reality, he considered that we don't achieve demonstrative knowledge – that kind of knowledge we call science — by looking at the imperfect material world. Truth is to be found through rational demonstrations, analogous to the demonstrations of geometry. [16] Applying this concept, Plato recommended that astronomy be studied in terms of geometrical models [17] and proposed that the elements were particles constructed on a geometrical basis. [18]

Aristotle (384–322 BC) disagreed with his teacher, Plato, in several important respects. While Aristotle agreed that truth must be eternal and unchanging, he maintained that we come to know the truth through the external world which we perceive with our senses. For Aristotle, directly observable things are real ideas (or as he called them, forms) only exist as they express themselves in matter, such as in living things, or in the mind of an observer or artisan. [19]

This theory of reality led to a radically different approach to science:

  • First, Aristotle emphasized observation of the material entities which embody the forms.
  • Second, he played down the importance of mathematics.
  • Third, he emphasized the process of change where Plato had emphasized eternal unchanging ideas.
  • Fourth, he reduced the importance of Plato's ideas to one of four causal factors.

As this last point suggests, Aristotle's concept of causes was less limited than ours. He distinguished four causes:

  • the matter of which a thing was made (the material cause).
  • the form into which it was made (the formal cause something similar to Plato's ideas).
  • the agent who made the thing (the moving or efficient cause).
  • the purpose for which the thing was made (the final cause).

Aristotle's emphasis upon causes fundamentally shaped the later development of science by insisting that scientific knowledge, what the Greeks called episteme and the Romans scientia, is knowledge of necessary causes. He and his followers would not accept mere description or prediction as science. In view of this disagreement with Plato, Aristotle established his own school, the Lyceum, which further developed and transmitted his approach to the investigation of nature.

Most characteristic of Aristotle's causes is his final cause, the purpose for which a thing is made. He came to this insight through his biological researches, in which he noted that the organs of animals serve a particular function.

The absence of chance and the serving of ends are found in the works of nature especially. And the end for the sake of which a thing has been constructed or has come to be belongs to what is beautiful. [20]

Thus Aristotle was one of the most prolific natural philosophers of Antiquity. He made countless observations of the structure and habits of animals, especially those in the sea at Lesbos. He also made many observations about the large-scale workings of the universe, which led to his development of a comprehensive theory of physics. For example, he developed a version of the classical theory of the elements (earth, water, fire, air, and aether). In his theory, the light elements (fire and air) have a natural tendency to move away from the center of the universe while the heavy elements (earth and water) have a natural tendency to move toward the center of the universe, thereby forming a spherical earth. Since the celestial bodies – that is, the planets and stars – were seen to move in circles, he concluded that they must be made of a fifth element, which he called Aether. [21]

Aristotle could point to the falling stone, rising flames, or pouring water to illustrate his theory. His laws of motion emphasized the common observation that friction was an omnipresent phenomenon – that any body in motion would, unless acted upon, come to rest. He also proposed that heavier objects fall faster, and that voids were impossible.

Theophrastus Edit

Aristotle's successor at the Lyceum was Theophrastus, who wrote valuable books describing plant and animal life. His works are regarded as the first to put botany and zoology on a systematic footing. He also produced one of the first works on mineralogy, with descriptions of ores and minerals known to the world at that time. He made some shrewd observations of their properties. For example, he made the first known reference to the phenomenon, now known to be caused by pyroelectricity, that the mineral tourmaline attracts straws and bits of wood when heated. [22] Pliny the Elder makes clear references to his use of the work in his Natural History of 77 AD, while updating and making much new information available on minerals himself. From both these early texts was to emerge the science of mineralogy, and ultimately geology. Both authors describe the sources of the minerals they discuss in the various mines exploited in their time, so their works should be regarded not just as early scientific texts, but also important for the history of engineering and the history of technology. Pliny is especially significant because he provides full bibliographic details of the earlier authors and their works he uses and consults. Because his encyclopedia survived the Dark Ages, we know of these lost works, even if the texts themselves have disappeared. The book was one of the first to be printed in 1489, and became a standard reference work for Renaissance scholars, as well as an inspiration for the development of a scientific and rational approach to the world.

The important legacy of this period of Greek science included substantial advances in factual knowledge, especially in anatomy, zoology, botany, mineralogy and astronomy an awareness of the importance of certain scientific problems, especially those related to the problem of change and its causes and a recognition of the methodological importance of applying mathematics to natural phenomena and of undertaking empirical research. [23]

The military campaigns of Alexander the Great spread Greek thought to Egypt, Asia Minor, Persia, up to the Indus River. The resulting Hellenistic civilization produced seats of learning in Alexandria in Egypt and Antioch in Syria along with Greek speaking populations across several monarchies. Hellenistic science differed from Greek science in at least two ways: first, it benefited from the cross-fertilization of Greek ideas with those that had developed in the larger Hellenistic world secondly, to some extent, it was supported by royal patrons in the kingdoms founded by Alexander's successors. Especially important to Hellenistic science was the city of Alexandria in Egypt, which became a major center of scientific research in the 3rd century BC. Two institutions established there during the reigns of Ptolemy I Soter (reigned 323–283 BC) and Ptolemy II Philadelphus (reigned 281–246 BC) were the Library and the Museum. Unlike Plato's Academy and Aristotle's Lyceum, these institutions were officially supported by the Ptolemies although the extent of patronage could be precarious, depending on the policies of the current ruler. [24]

Hellenistic scholars frequently employed the principles developed in earlier Greek thought: the application of mathematics and deliberate empirical research, in their scientific investigations. [25]

The interpretation of Hellenistic science varies widely. At one extreme is the view of English classical scholar Cornford, who believed that "all the most important and original work was done in the three centuries from 600 to 300 BC". [26] At the other end is the view of Italian physicist and mathematician Lucio Russo, who claims that the scientific method was actually born in the 3rd century BCE, only to be forgotten during the Roman period and not revived again until the Renaissance. [27]

Technology Edit

The level of Hellenistic achievement in astronomy and engineering is impressively shown by the Antikythera mechanism (150–100 BCE). It is a 37-gear mechanical computer which computed the motions of the Sun and Moon, including lunar and solar eclipses predicted on the basis of astronomical periods believed to have been learned from the Babylonians. [28] Devices of this sort are not known to have been engineered again until the 10th century, when a simpler eight-geared luni-solar calculator incorporated into an astrolabe was described by Persian scholar Al-Biruni. [29] [ failed verification ] Similarly complex devices were also developed by other Muslim engineers and astronomers during the Middle Ages. [28]

Medicine Edit

In medicine, Herophilos (335–280 BCE) was the first to base his conclusions on dissection of the human body and to describe the nervous system. For this, he is often called as "the father of anatomy" [30]

Mathematics Edit

Beginning with the Hellenistic period, Greek mathematics and astronomy reached a level of sophistication not matched for several centuries afterwards. Much of the work represented by scholars active in this period was of a very advanced level. There is also evidence of combining mathematical knowledge with high levels of technical expertise, as found for instance in construction of simple analogical devices such as the Antikythera mechanism, or in Eratosthenes' (276 – 195 BCE) measurement of the distance between the Sun and the Earth and the size of the Earth. [32]

Although few in number, Hellenistic mathematicians actively communicated with each other publication consisted of passing and copying someone's work among colleagues. Among their accomplishments is the work of Euclid (325 – 265 BCE), which includes the Elements, a canon of geometry and elementary number theory for many centuries. Archimedes (287 – 212 BCE) found many remarkable results, such as the sum of an infinite geometric series in Quadrature of the Parabola, an approximation to the value π in Measurement of the Circle, and a nomenclature to express very large numbers in the Sand Reckoner.

The most characteristic product of Greek mathematics may be the theory of conic sections, which was largely developed in the Hellenistic period, primarily by Apollonius (262 – 190 BCE). The methods used made no explicit use of algebra, nor trigonometry, the latter appearing around the time of Hipparchus (190 – 120 BCE).

Astronomy Edit

Aristarchus of Samos (310 – 230 BCE) was an ancient Greek astronomer and mathematician who presented the first known heliocentric model that placed the Sun at the center of the known universe, with the Earth revolving around the Sun once a year and rotating about its axis once a day. Aristarchus also estimated the sizes of the Sun and Moon as compared to Earth's size, and the distances to the Sun and Moon. His heliocentric model did not find many adherents in antiquity but did influence some early modern astronomers, such as Nicolaus Copernicus, who was aware of the heliocentric theory of Aristarchus. [33]

In the 2nd century BC, Hipparchus discovered precession, calculated the size and distance of the Moon and invented the earliest known astronomical devices such as the astrolabe. [34] Hipparchus also created a comprehensive catalog of 1020 stars, and most of the constellations of the northern hemisphere derive from Greek astronomy. [35] [36] It has recently been claimed that a celestial globe based on Hipparchus's star catalog sits atop the broad shoulders of a large 2nd-century Roman statue known as the Farnese Atlas. [37]

Science in the Roman Empire period was concerned with systematizing knowledge gained in the preceding Hellenistic period and the knowledge from the vast areas the Romans had conquered. It was largely their work that would be passed on to later civilizations. [ citation needed ]

Even though science continued under the Roman Empire, Latin texts were mainly compilations drawing on earlier Greek work. Advanced scientific research and teaching continued to be carried on in Greek. Such Greek and Hellenistic works as survived were preserved and developed later in the Byzantine Empire and then in the Islamic world. Late Roman attempts to translate Greek writings into Latin had limited success, and direct knowledge of most ancient Greek texts only reached western Europe from the 12th century onwards. [38]

Pliny Edit

Of particular importance is the Naturalis Historia of Pliny the Elder published in 77 CE, one of the most extensive compilations of the natural world which survived the Dark Ages. Pliny does not simply list materials and objects but also seeks explanations of phenomena. Thus he is the first to correctly describe the origin of amber as being the fossilized resin of pine trees. He makes the inference from the observation of trapped insects within some amber samples. The Naturalis Historia divides neatly into the organic world of plants and animals, and the realm of inorganic matter, although there are frequent digressions in each section. He is especially interested in not just describing the occurrence of plants, animals and insects, but also their exploitation (or abuse) by man. The description of metals and minerals is particularly detailed, and valuable as being the most extensive compilation still available from the ancient world. Although much of the work was compiled by judicious use of written sources, Pliny gives an eye witness account of gold mining in Spain, where he was stationed as an officer. [ citation needed ]

Ptolemy Edit

In the middle decades of the second century CE, Claudius Ptolemy carried out a massive scientific program centering on the writing of about a dozen books on astronomy, astrology, optics, harmonics, and cartography. In spite of their severe style and uncompromising technicality, a great part of them were preserved down the centuries, almost the sole remnants of their kind of scientific writing from antiquity. Though ranging widely in subject matter, these books revolve around two great themes: mathematical modelling of phenomena, and methods of visual representation of physical reality. [39]

A good representative of Ptolemy's work is his systematized study of astronomy. Ptolemy drew on the work of his predecessors to build astronomy upon a secure empirical basis and to demonstrate the relationship between astronomical observations and the resulting astronomical theory. His Almagest defined the method and subject matter of future astronomical research and the Ptolemaic system became the dominant model for the motions of the heavens until the seventeenth century. [40]

Galen Edit

In like manner, the Roman-era physician Galen codified and somewhat built upon Hellenistic knowledge of anatomy and physiology. His careful dissections and observations of dogs, pigs, and Barbary apes, his descriptions (based on these and the works of earlier authors) of such structures as the nervous system, heart, and kidneys, and his demonstrations that, for instance, arteries carry blood instead of air became a central part of medical knowledge for well over a thousand years. [ citation needed ]

Hero Edit

Hero of Alexandria was a Greco-Egyptian mathematician and engineer who is often considered to be the greatest experimenter of antiquity. [41] Among his most famous inventions was a windwheel, constituting the earliest instance of wind harnessing on land, and a well-recognized description of a steam-powered device called an aeolipile, which was the first-recorded steam engine.


Greek Science - History

Greece and the Birth of Science

The new "Greek" approach to thinking about nature was perhaps the greatest breakthrough ever made in human thought. So far as we can tell, it began about 600 B.C., in Ionia, the southern coast of Asian Turkey, where there were a number of prosperous Greek city-states. Sadly, much of the record is lost (for example, only the first sentence of what is believed to be the first book on science - by Anaximander of Miletus - has survived). Scholars piece the history together from fragments reported by others, frequently centuries after the original writings. From these fragments, though, it is clear that Anaximander, his colleague Thales, and others were raising for the first time broad questions about what unifying themes could explain the behavior of nature.

Astronomy provides only an example of how this new mode of thought sprang forth, but a good one. We can appreciate the advance by comparing with Maya astronomy, which actually came a thousand years after the peak of Greek power and influence, but was independent of them and is a highly developed example of astronomy as it was practiced in other societies prior to the Greeks. In general, as with the Maya, societies that generated enough wealth to invest in a high level of astronomical research were all highly centralized, with a totally dominant ruling class. Astronomy was practiced by an elite society of priests who served the rulers. Astronomy served as a very sophisticated astrology, in which events in the sky were used to forecast the future and help the rulers make critical decisions. The observations were also used to awe the populace, reinforcing the power of the ruling order (as with Stonehenge as well as El Castillo). Astronomy was the province of religion that was part of an oppressive ruling structure.

The Greek civilization had a remarkably different organization, centered on a large number of independent city-states. They had a strong concept of individual rights for the citizens of these states (although ironically, most of the population might be slaves that they had acquired in wars among each other (or with other groups)). Religion was practiced by all of the citizens, any one of whom could go to a temple and make an offering to the appropriate deity. Although there were exceptions, many of the city-states operated on the principle that rulers served the people and did not necessarily rule for life, but could be removed. Thus, the Greek lifestyle ran strongly counter to the oppressive, dominant government/religions that had ruled other wealthy societies.

The combination of efficient farming, the contributions of slaves in doing menial work, the government and religion that responded to the needs of the people, and an efficient social structure that allowed generation of substantial wealth, all worked together to produce a new phenomenon. The Greeks were able to put substantial resources into science, mathematics, philosophy, and literature. Along with these interests came the need to educate, and a teacher class grew up. The most outstanding of these teachers became famous and attracted many pupils to large schools. They thought deeply about nature, mathematics, and philosophy. They left a heritage of important writings on these subjects. Euclid developed virtually the entire subject of geometry and also contributed to optics. Aristotle was a great observer of nature and left many volumes describing the results. Archemides contributed to physics and mathematics. Eudoxus developed a form of calculus. Hippochratus left writings on the practice of medicine, as well as the famous oath that guides all doctors: "Do no harm."

When the city-state structure was threatened, it was forcibly restored. For example, Athens collected contributions from a network of other states to help support its powerful navy in protecting them. Under Pericles, about 430 B.C., these payments grew quickly and the navy was used more to enforce payment than to protect.

Sparta and its allies successfully restored the independence of the city-states in the Peloponesian Wars. Athens' imperial ambitions were so immense that it weakened its ability to fight Sparta by invading Sicily in the middle of these wars, where it was disastrously defeated by the navy and army of Syracuse. When the Spartan alliance was finally victorious, they fortunately violated Greek tradition and did not destroy Athens. Instead, they let it survive as a center of learning and intellectual influence, and science and philosophy continued to flourish. However, by about 100 - 200 B.C., power had become highly centralized in the "Hellenic States." Creative Greek science died out in parallel with this trend.

The Greek astronomers had access to a long tradition of accurate observations by the Babylonians. Babylonian astronomy was remarkably similar in many ways to that of the Maya (but was carried out two millennia earlier) Very detailed observations over centuries, combined with sophisticated mathematics, allowed the Babylonian astronomers to determine accurately the periods of the motions of the planets, and to predict specific events such as when Venus would be farthest from the sun . However, they had made no effort to probe further, into underlying causes.

Greek astronomy was strongly influenced by the followers of Pythagoras, who felt that everything could be understood in terms of special numbers - they even invented a hidden Earth to raise the number of planets to the desired count. The Pythagoreans originated the idea that the planets moved on circular orbits and at constant speed.

  • Anaximander envisioned the sky to be a vast fluid, extending shoreless and endless. The earth was a whirlpool in this fluid.
  • Anaximenes proposed that everything is made of air, compressed for some things and rarefied for others.Thus, air itself is compressible, but the products such as water, wood, etc. are fully compressed and cannot be further compacted.
  • Heraclitus proposed that everything is made of the four elements fire, air, water, and earth.
  • Pythagoras, as we have already mentioned, thought that everything could be explained in terms of relations among the numbers. His school proposed that 10, as the sum of of the first four (1 + 2 + 3 + 4 = 10), was the perfect number and even invented a new planet to make ten of them.
  • Democritus advocated that all things are made of minute atoms, which have no weight and move in a void of infinite space.
  • Plato imagined an ideal world, with all things in our world fashioned imperfectly after counterparts in the ideal one.
  • Aristotle thought that atoms for various basic objects had the underlying character of that entity - cats are made of atoms with catness, wood of atoms with woodness, and so forth.

We should not give the Greeks too much credit when one of these theories (for example of atoms) anticipates a product of modern science. However, we must give immense credit for the pattern of thought that they introduced, the concept that things could be understood in terms of underlying causes and that these explanations could be tested to see if they were correct. These principles define the scientific method, as we still practice it. Their new method of thought has proven very powerful in making progress in our understanding of nature. Aristotle stated it more clearly than anyone since: "There is no science except of the general." (de Santillana, p. 210).


Contents

In prehistoric times, knowledge and technique were passed from generation to generation in an oral tradition. For instance, the domestication of maize for agriculture has been dated to about 9,000 years ago in southern Mexico, before the development of writing systems. [26] [27] [28] Similarly, archaeological evidence indicates the development of astronomical knowledge in preliterate societies. [29] [30]

The oral tradition of preliterate societies had several features, the first of which was its fluidity. [3] New information was constantly absorbed and adjusted to new circumstances or community needs. There were no archives or reports. This fluidity was closely related to the practical need to explain and justify a present state of affairs. [3] Another feature was the tendency to describe the universe as just sky and earth, with a potential underworld. They were also prone to identify causes with beginnings, thereby providing a historical origin with an explanation. There was also a reliance on a "medicine man" or "wise woman" for healing, knowledge of divine or demonic causes of diseases, and in more extreme cases, for rituals such as exorcism, divination, songs, and incantations. [3] Finally, there was an inclination to unquestioningly accept explanations that might be deemed implausible in more modern times while at the same time not being aware that such credulous behaviors could have posed problems. [3]

The development of writing enabled humans to store and communicate knowledge across generations with much greater accuracy. Its invention was a prerequisite for the development of philosophy and later science in ancient times. [3] Moreover, the extent to which philosophy and science would flourish in ancient times depended on the efficiency of a writing system (e.g., use of alphabets). [3]

The earliest roots of science can be traced to Ancient Egypt and Mesopotamia in around 3000 to 1200 BCE. [3]

Ancient Egypt Edit

Number system and geometry Edit

Starting in around 3000 BCE, the ancient Egyptians developed a numbering system that was decimal in character and had orientated their knowledge of geometry to solving practical problems such as those of surveyors and builders. [3] They even developed an official calendar that contained twelve months, thirty days each, and five days at the end of the year. [3] Their development of geometry was a necessary outgrowth of surveying to preserve the layout and ownership of farmland, which was flooded annually by the Nile river. The 3-4-5 right triangle and other rules of geometry were used to build rectilinear structures, and the post and lintel architecture of Egypt.

Disease and healing Edit

Egypt was also a center of alchemy research for much of the Mediterranean. Based on the medical papyri written in the 2500–1200 BCE, the ancient Egyptians believed that disease was mainly caused by the invasion of bodies by evil forces or spirits. [3] Thus, in addition to using medicines, their healing therapies included prayer, incantation, and ritual. [3] The Ebers Papyrus, written in around 1600 BCE, contains medical recipes for treating diseases related to the eyes, mouths, skins, internal organs, and extremities as well as abscesses, wounds, burns, ulcers, swollen glands, tumors, headaches, and even bad breath. The Edwin Smith papyrus, written at about the same time, contains a surgical manual for treating wounds, fractures, and dislocations. The Egyptians believed that the effectiveness of their medicines depended on the preparation and administration under appropriate rituals. [3] Medical historians believe that ancient Egyptian pharmacology, for example, was largely ineffective. [31] Both the Ebers and Edwin Smith papyri applied the following components to the treatment of disease: examination, diagnosis, treatment, and prognosis, [32] which display strong parallels to the basic empirical method of science and, according to G.E.R. Lloyd, [33] played a significant role in the development of this methodology.

Calendar Edit

The ancient Egyptians even developed an official calendar that contained twelve months, thirty days each, and five days at the end of the year. [3] Unlike the Babylonian calendar or the ones used in Greek city-states at the time, the official Egyptian calendar was much simpler as it was fixed and did not take lunar and solar cycles into consideration. [3]

Mesopotamia Edit

The ancient Mesopotamians had extensive knowledge about the chemical properties of clay, sand, metal ore, bitumen, stone, and other natural materials, and applied this knowledge to practical use in manufacturing pottery, faience, glass, soap, metals, lime plaster, and waterproofing. Metallurgy required knowledge about the properties of metals. Nonetheless, the Mesopotamians seem to have had little interest in gathering information about the natural world for the mere sake of gathering information and were far more interested in studying the manner in which the gods had ordered the universe. Biology of non-human organisms was generally only written about in the context of mainstream academic disciplines. Animal physiology was studied extensively for the purpose of divination the anatomy of the liver, which was seen as an important organ in haruspicy, was studied in particularly intensive detail. Animal behavior was also studied for divinatory purposes. Most information about the training and domestication of animals was probably transmitted orally without being written down, but one text dealing with the training of horses has survived. [34]

Mesopotamian medicine Edit

The ancient Mesopotamians had no distinction between "rational science" and magic. [35] [36] [37] When a person became ill, doctors prescribed magical formulas to be recited as well as medicinal treatments. [35] [36] [37] [34] The earliest medical prescriptions appear in Sumerian during the Third Dynasty of Ur (c. 2112 BC – c. 2004 BC). [38] The most extensive Babylonian medical text, however, is the Diagnostic Handbook written by the ummânū, or chief scholar, Esagil-kin-apli of Borsippa, [39] during the reign of the Babylonian king Adad-apla-iddina (1069–1046 BC). [40] In East Semitic cultures, the main medicinal authority was a kind of exorcist-healer known as an āšipu. [35] [36] [37] The profession was generally passed down from father to son and was held in extremely high regard. [35] Of less frequent recourse was another kind of healer known as an asu, who corresponds more closely to a modern physician and treated physical symptoms using primarily folk remedies composed of various herbs, animal products, and minerals, as well as potions, enemas, and ointments or poultices. These physicians, who could be either male or female, also dressed wounds, set limbs, and performed simple surgeries. The ancient Mesopotamians also practiced prophylaxis and took measures to prevent the spread of disease. [34]

Mathematics Edit

The Mesopotamian cuneiform tablet Plimpton 322, dating to the eighteenth century BCE, records a number of Pythagorean triplets (3,4,5) (5,12,13) . [41] hinting that the ancient Mesopotamians might have been aware of the Pythagorean theorem over a millennium before Pythagoras. [42] [43] [44]

Astronomy and celestial divination Edit

In Babylonian astronomy, records of the motions of the stars, planets, and the moon are left on thousands of clay tablets created by scribes. Even today, astronomical periods identified by Mesopotamian proto-scientists are still widely used in Western calendars such as the solar year and the lunar month. Using these data they developed arithmetical methods to compute the changing length of daylight in the course of the year and to predict the appearances and disappearances of the Moon and planets and eclipses of the Sun and Moon. Only a few astronomers' names are known, such as that of Kidinnu, a Chaldean astronomer and mathematician. Kiddinu's value for the solar year is in use for today's calendars. Babylonian astronomy was "the first and highly successful attempt at giving a refined mathematical description of astronomical phenomena." According to the historian A. Aaboe, "all subsequent varieties of scientific astronomy, in the Hellenistic world, in India, in Islam, and in the West—if not indeed all subsequent endeavour in the exact sciences—depend upon Babylonian astronomy in decisive and fundamental ways." [45]

To the Babylonians and other Near Eastern cultures, messages from the gods or omens were concealed in all natural phenomena that could be deciphered and interpreted by those who are adept. [3] Hence, it was believed that the gods could speak through all terrestrial objects (e.g., animal entrails, dreams, malformed births, or even the color of a dog urinating on a person) and celestial phenomena. [3] Moreover, Babylonian astrology was inseparable from Babylonian astronomy.

Mathematical achievements from Mesopotamia had some influence on the development of mathematics in India, and there were confirmed transmissions of mathematical ideas between India and China, which were bidirectional. [46] Nevertheless, the mathematical and scientific achievements in India and particularly in China occurred largely independently [47] from those of Europe and the confirmed early influences that these two civilizations had on the development of science in Europe in the pre-modern era were indirect, with Mesopotamia and later the Islamic World acting as intermediaries. [46] The arrival of modern science, which grew out of the scientific revolution, in India and China and the greater Asian region in general can be traced to the scientific activities of Jesuit missionaries who were interested in studying the region's flora and fauna during the 16th and 17th century. [48]

India Edit

Indian astronomy and mathematics Edit

The earliest traces of mathematical knowledge in the Indian subcontinent appear with the Indus Valley Civilization (c. 4th millennium BCE

c. 3rd millennium BCE). The people of this civilization made bricks whose dimensions were in the proportion 4:2:1, considered favorable for the stability of a brick structure. [49] They also tried to standardize measurement of length to a high degree of accuracy. They designed a ruler—the Mohenjo-daro ruler—whose unit of length (approximately 1.32 inches or 3.4 centimetres) was divided into ten equal parts. Bricks manufactured in ancient Mohenjo-daro often had dimensions that were integral multiples of this unit of length. [50]

Indian astronomer and mathematician Aryabhata (476–550), in his Aryabhatiya (499) introduced the sine function in trigonometry. In 628 CE, Brahmagupta suggested that gravity was a force of attraction. [51] [52] He also lucidly explained the use of zero as both a placeholder and a decimal digit, along with the Hindu-Arabic numeral system now used universally throughout the world. Arabic translations of the two astronomers' texts were soon available in the Islamic world, introducing what would become Arabic numerals to the Islamic world by the 9th century. [53] [54] During the 14th–16th centuries, the Kerala school of astronomy and mathematics made significant advances in astronomy and especially mathematics, including fields such as trigonometry and analysis. In particular, Madhava of Sangamagrama is considered the "founder of mathematical analysis". [55]

In the Tantrasangraha treatise, Nilakantha Somayaji's updated the Aryabhatan model for the interior planets, Mercury, and Venus and the equation that he specified for the center of these planets was more accurate than the ones in European or Islamic astronomy until the time of Johannes Kepler in the 17th century. [56]

The first textual mention of astronomical concepts comes from the Vedas, religious literature of India. [57] According to Sarma (2008): "One finds in the Rigveda intelligent speculations about the genesis of the universe from nonexistence, the configuration of the universe, the spherical self-supporting earth, and the year of 360 days divided into 12 equal parts of 30 days each with a periodical intercalary month.". [57] The first 12 chapters of the Siddhanta Shiromani, written by Bhāskara in the 12th century, cover topics such as: mean longitudes of the planets true longitudes of the planets the three problems of diurnal rotation syzygies lunar eclipses solar eclipses latitudes of the planets risings and settings the moon's crescent conjunctions of the planets with each other conjunctions of the planets with the fixed stars and the patas of the sun and moon. The 13 chapters of the second part cover the nature of the sphere, as well as significant astronomical and trigonometric calculations based on it.

Grammar Edit

Some of the earliest linguistic activities can be found in Iron Age India (1st millennium BCE) with the analysis of Sanskrit for the purpose of the correct recitation and interpretation of Vedic texts. The most notable grammarian of Sanskrit was Pāṇini (c. 520–460 BCE), whose grammar formulates close to 4,000 rules for Sanskrit. Inherent in his analytic approach are the concepts of the phoneme, the morpheme and the root. The Tolkāppiyam text, composed in the early centuries of the common era, [58] is a comprehensive text on Tamil grammar, which includes sutras on orthography, phonology, etymology, morphology, semantics, prosody, sentence structure and the significance of context in language.

Medicine Edit

Findings from Neolithic graveyards in what is now Pakistan show evidence of proto-dentistry among an early farming culture. [59] The ancient text Suśrutasamhitā of Suśruta describes procedures on various forms of surgery, including rhinoplasty, the repair of torn ear lobes, perineal lithotomy, cataract surgery, and several other excisions and other surgical procedures.

Politics and state Edit

An ancient Indian treatise on statecraft, economic policy and military strategy by Kautilya [60] and Viṣhṇugupta, [61] who are traditionally identified with Chāṇakya (c. 350–283 BCE). In this treatise, the behaviors and relationships of the people, the King, the State, the Government Superintendents, Courtiers, Enemies, Invaders, and Corporations are analysed and documented. Roger Boesche describes the Arthaśāstra as "a book of political realism, a book analysing how the political world does work and not very often stating how it ought to work, a book that frequently discloses to a king what calculating and sometimes brutal measures he must carry out to preserve the state and the common good." [62]

China Edit

Chinese mathematics Edit

From the earliest the Chinese used a positional decimal system on counting boards in order to calculate. To express 10, a single rod is placed in the second box from the right. The spoken language uses a similar system to English: e.g. four thousand two hundred seven. No symbol was used for zero. By the 1st century BCE, negative numbers and decimal fractions were in use and The Nine Chapters on the Mathematical Art included methods for extracting higher order roots by Horner's method and solving linear equations and by Pythagoras' theorem. Cubic equations were solved in the Tang dynasty and solutions of equations of order higher than 3 appeared in print in 1245 CE by Ch'in Chiu-shao. Pascal's triangle for binomial coefficients was described around 1100 by Jia Xian.

Although the first attempts at an axiomatisation of geometry appear in the Mohist canon in 330 BCE, Liu Hui developed algebraic methods in geometry in the 3rd century CE and also calculated pi to 5 significant figures. In 480, Zu Chongzhi improved this by discovering the ratio 355 113 <113>>> which remained the most accurate value for 1200 years.

Astronomical observations Edit

Astronomical observations from China constitute the longest continuous sequence from any civilization and include records of sunspots (112 records from 364 BCE), supernovas (1054), lunar and solar eclipses. By the 12th century, they could reasonably accurately make predictions of eclipses, but the knowledge of this was lost during the Ming dynasty, so that the Jesuit Matteo Ricci gained much favour in 1601 by his predictions. [64] By 635 Chinese astronomers had observed that the tails of comets always point away from the sun.

From antiquity, the Chinese used an equatorial system for describing the skies and a star map from 940 was drawn using a cylindrical (Mercator) projection. The use of an armillary sphere is recorded from the 4th century BCE and a sphere permanently mounted in equatorial axis from 52 BCE. In 125 CE Zhang Heng used water power to rotate the sphere in real time. This included rings for the meridian and ecliptic. By 1270 they had incorporated the principles of the Arab torquetum.

In the Song Empire (960–1279) of Imperial China, Chinese scholar-officials unearthed, studied, and cataloged ancient artifacts.

Inventions Edit

To better prepare for calamities, Zhang Heng invented a seismometer in 132 CE which provided instant alert to authorities in the capital Luoyang that an earthquake had occurred in a location indicated by a specific cardinal or ordinal direction. [65] Although no tremors could be felt in the capital when Zhang told the court that an earthquake had just occurred in the northwest, a message came soon afterwards that an earthquake had indeed struck 400 km (248 mi) to 500 km (310 mi) northwest of Luoyang (in what is now modern Gansu). [66] Zhang called his device the 'instrument for measuring the seasonal winds and the movements of the Earth' (Houfeng didong yi 候风地动仪), so-named because he and others thought that earthquakes were most likely caused by the enormous compression of trapped air. [67]

There are many notable contributors to early Chinese disciplines, inventions, and practices throughout the ages. One of the best examples would be the medieval Song Chinese Shen Kuo (1031–1095), a polymath and statesman who was the first to describe the magnetic-needle compass used for navigation, discovered the concept of true north, improved the design of the astronomical gnomon, armillary sphere, sight tube, and clepsydra, and described the use of drydocks to repair boats. After observing the natural process of the inundation of silt and the find of marine fossils in the Taihang Mountains (hundreds of miles from the Pacific Ocean), Shen Kuo devised a theory of land formation, or geomorphology. He also adopted a theory of gradual climate change in regions over time, after observing petrified bamboo found underground at Yan'an, Shaanxi province. If not for Shen Kuo's writing, [68] the architectural works of Yu Hao would be little known, along with the inventor of movable type printing, Bi Sheng (990–1051). Shen's contemporary Su Song (1020–1101) was also a brilliant polymath, an astronomer who created a celestial atlas of star maps, wrote a treatise related to botany, zoology, mineralogy, and metallurgy, and had erected a large astronomical clocktower in Kaifeng city in 1088. To operate the crowning armillary sphere, his clocktower featured an escapement mechanism and the world's oldest known use of an endless power-transmitting chain drive. [69] [70]

The Jesuit China missions of the 16th and 17th centuries "learned to appreciate the scientific achievements of this ancient culture and made them known in Europe. Through their correspondence European scientists first learned about the Chinese science and culture." [71] Western academic thought on the history of Chinese technology and science was galvanized by the work of Joseph Needham and the Needham Research Institute. Among the technological accomplishments of China were, according to the British scholar Needham, early seismological detectors (Zhang Heng in the 2nd century), the water-powered celestial globe (Zhang Heng), matches, the independent invention of the decimal system, dry docks, sliding calipers, the double-action piston pump, cast iron, the blast furnace, the iron plough, the multi-tube seed drill, the wheelbarrow, the suspension bridge, the winnowing machine, the rotary fan, the parachute, natural gas as fuel, the raised-relief map, the propeller, the crossbow, and a solid fuel rocket, the multistage rocket, the horse collar, along with contributions in logic, astronomy, medicine, and other fields.

However, cultural factors prevented these Chinese achievements from developing into "modern science". According to Needham, it may have been the religious and philosophical framework of Chinese intellectuals which made them unable to accept the ideas of laws of nature:

It was not that there was no order in nature for the Chinese, but rather that it was not an order ordained by a rational personal being, and hence there was no conviction that rational personal beings would be able to spell out in their lesser earthly languages the divine code of laws which he had decreed aforetime. The Taoists, indeed, would have scorned such an idea as being too naïve for the subtlety and complexity of the universe as they intuited it. [72]

The contributions of the Ancient Egyptians and Mesopotamians in the areas of astronomy, mathematics, and medicine had entered and shaped Greek natural philosophy of classical antiquity, whereby formal attempts were made to provide explanations of events in the physical world based on natural causes. [3] [4] Inquiries were also aimed at such practical goals such as establishing a reliable calendar or determining how to cure a variety of illnesses. The ancient people who were considered the first scientists may have thought of themselves as natural philosophers, as practitioners of a skilled profession (for example, physicians), or as followers of a religious tradition (for example, temple healers).

Pre-socratics Edit

The earliest Greek philosophers, known as the pre-Socratics, [73] provided competing answers to the question found in the myths of their neighbors: "How did the ordered cosmos in which we live come to be?" [74] The pre-Socratic philosopher Thales (640–546 BCE) of Miletus, identified by later authors such as Aristotle as the first of the Ionian philosophers, [3] postulated non-supernatural explanations for natural phenomena. For example, that land floats on water and that earthquakes are caused by the agitation of the water upon which the land floats, rather than the god Poseidon. [75] Thales' student Pythagoras of Samos founded the Pythagorean school, which investigated mathematics for its own sake, and was the first to postulate that the Earth is spherical in shape. [76] Leucippus (5th century BCE) introduced atomism, the theory that all matter is made of indivisible, imperishable units called atoms. This was greatly expanded on by his pupil Democritus and later Epicurus.

Natural philosophy Edit

Plato and Aristotle produced the first systematic discussions of natural philosophy, which did much to shape later investigations of nature. Their development of deductive reasoning was of particular importance and usefulness to later scientific inquiry. Plato founded the Platonic Academy in 387 BCE, whose motto was "Let none unversed in geometry enter here", and turned out many notable philosophers. Plato's student Aristotle introduced empiricism and the notion that universal truths can be arrived at via observation and induction, thereby laying the foundations of the scientific method. [77] Aristotle also produced many biological writings that were empirical in nature, focusing on biological causation and the diversity of life. He made countless observations of nature, especially the habits and attributes of plants and animals on Lesbos, classified more than 540 animal species, and dissected at least 50. [78] Aristotle's writings profoundly influenced subsequent Islamic and European scholarship, though they were eventually superseded in the Scientific Revolution. [79] [80]

The important legacy of this period included substantial advances in factual knowledge, especially in anatomy, zoology, botany, mineralogy, geography, mathematics and astronomy an awareness of the importance of certain scientific problems, especially those related to the problem of change and its causes and a recognition of the methodological importance of applying mathematics to natural phenomena and of undertaking empirical research. [81] In the Hellenistic age scholars frequently employed the principles developed in earlier Greek thought: the application of mathematics and deliberate empirical research, in their scientific investigations. [82] Thus, clear unbroken lines of influence lead from ancient Greek and Hellenistic philosophers, to medieval Muslim philosophers and scientists, to the European Renaissance and Enlightenment, to the secular sciences of the modern day. Neither reason nor inquiry began with the Ancient Greeks, but the Socratic method did, along with the idea of Forms, great advances in geometry, logic, and the natural sciences. According to Benjamin Farrington, former Professor of Classics at Swansea University:

"Men were weighing for thousands of years before Archimedes worked out the laws of equilibrium they must have had practical and intuitional knowledge of the principles involved. What Archimedes did was to sort out the theoretical implications of this practical knowledge and present the resulting body of knowledge as a logically coherent system."

"With astonishment we find ourselves on the threshold of modern science. Nor should it be supposed that by some trick of translation the extracts have been given an air of modernity. Far from it. The vocabulary of these writings and their style are the source from which our own vocabulary and style have been derived." [83]

Greek astronomy Edit

The astronomer Aristarchus of Samos was the first known person to propose a heliocentric model of the solar system, while the geographer Eratosthenes accurately calculated the circumference of the Earth. Hipparchus (c. 190 – c. 120 BCE) produced the first systematic star catalog. The level of achievement in Hellenistic astronomy and engineering is impressively shown by the Antikythera mechanism (150–100 BCE), an analog computer for calculating the position of planets. Technological artifacts of similar complexity did not reappear until the 14th century, when mechanical astronomical clocks appeared in Europe. [84]

Hellenistic medicine Edit

In medicine, Hippocrates (c. 460 BC – c. 370 BCE) and his followers were the first to describe many diseases and medical conditions and developed the Hippocratic Oath for physicians, still relevant and in use today. Herophilos (335–280 BCE) was the first to base his conclusions on dissection of the human body and to describe the nervous system. Galen (129 – c. 200 CE) performed many audacious operations—including brain and eye surgeries— that were not tried again for almost two millennia.

Greek mathematics Edit

In Hellenistic Egypt, the mathematician Euclid laid down the foundations of mathematical rigor and introduced the concepts of definition, axiom, theorem and proof still in use today in his Elements, considered the most influential textbook ever written. [86] Archimedes, considered one of the greatest mathematicians of all time, [87] is credited with using the method of exhaustion to calculate the area under the arc of a parabola with the summation of an infinite series, and gave a remarkably accurate approximation of pi. [88] He is also known in physics for laying the foundations of hydrostatics, statics, and the explanation of the principle of the lever.

Other developments Edit

Theophrastus wrote some of the earliest descriptions of plants and animals, establishing the first taxonomy and looking at minerals in terms of their properties such as hardness. Pliny the Elder produced what is one of the largest encyclopedias of the natural world in 77 CE, and must be regarded as the rightful successor to Theophrastus. For example, he accurately describes the octahedral shape of the diamond, and proceeds to mention that diamond dust is used by engravers to cut and polish other gems owing to its great hardness. His recognition of the importance of crystal shape is a precursor to modern crystallography, while mention of numerous other minerals presages mineralogy. He also recognises that other minerals have characteristic crystal shapes, but in one example, confuses the crystal habit with the work of lapidaries. He was also the first to recognise that amber was a fossilized resin from pine trees because he had seen samples with trapped insects within them.

The development of the field of archaeology has it roots with history and with those who were interested in the past, such as kings and queens who wanted to show past glories of their respective nations. The 5th-century-BCE Greek historian Herodotus was the first scholar to systematically study the past and perhaps the first to examine artifacts.

Greek scholarship under Roman rule Edit

During the rule of Rome, famous historians such as Polybius, Livy and Plutarch documented the rise of the Roman Republic, and the organization and histories of other nations, while statesmen like Julius Caesar, Cicero, and others provided examples of the politics of the republic and Rome's empire and wars. The study of politics during this age was oriented toward understanding history, understanding methods of governing, and describing the operation of governments.

The Roman conquest of Greece did not diminish learning and culture in the Greek provinces. [89] On the contrary, the appreciation of Greek achievements in literature, philosophy, politics, and the arts by Rome's upper class coincided with the increased prosperity of the Roman Empire. Greek settlements had existed in Italy for centuries and the ability to read and speak Greek was not uncommon in Italian cities such as Rome. [89] Moreover, the settlement of Greek scholars in Rome, whether voluntarily or as slaves, gave Romans access to teachers of Greek literature and philosophy. Conversely, young Roman scholars also studied abroad in Greece and upon their return to Rome, were able to convey Greek achievements to their Latin leadership. [89] And despite the translation of a few Greek texts into Latin, Roman scholars who aspired to the highest level did so using the Greek language. The Roman statesman and philosopher Cicero (106 – 43 BCE) was a prime example. He had studied under Greek teachers in Rome and then in Athens and Rhodes. He mastered considerable portions of Greek philosophy, wrote Latin treatises on several topics, and even wrote Greek commentaries of Plato's Timaeus as well as a Latin translation of it, which has not survived. [89]

In the beginning, support for scholarship in Greek knowledge was almost entirely funded by the Roman upper class. [89] There were all sorts of arrangements, ranging from a talented scholar being attached to a wealthy household to owning educated Greek-speaking slaves. [89] In exchange, scholars who succeeded at the highest level had an obligation to provide advice or intellectual companionship to their Roman benefactors, or to even take care of their libraries. The less fortunate or accomplished ones would teach their children or perform menial tasks. [89] The level of detail and sophistication of Greek knowledge was adjusted to suit the interests of their Roman patrons. That meant popularizing Greek knowledge by presenting information that were of practical value such as medicine or logic (for courts and politics) but excluding subtle details of Greek metaphysics and epistemology. Beyond the basics, the Romans did not value natural philosophy and considered it an amusement for leisure time. [89]

Commentaries and encyclopedias were the means by which Greek knowledge was popularized for Roman audiences. [89] The Greek scholar Posidonius (c. 135-c. 51 BCE), a native of Syria, wrote prolifically on history, geography, moral philosophy, and natural philosophy. He greatly influenced Latin writers such as Marcus Terentius Varro (116-27 BCE), who wrote the encyclopedia Nine Books of Disciplines, which covered nine arts: grammar, rhetoric, logic, arithmetic, geometry, astronomy, musical theory, medicine, and architecture. [89] The Disciplines became a model for subsequent Roman encyclopedias and Varro's nine liberal arts were considered suitable education for a Roman gentleman. The first seven of Varro's nine arts would later define the seven liberal arts of medieval schools. [89] The pinnacle of the popularization movement was the Roman scholar Pliny the Elder (23/24–79 CE), a native of northern Italy, who wrote several books on the history of Rome and grammar. His most famous work was his voluminous Natural History. [89]

After the death of the Roman Emperor Marcus Aurelius in 180 CE, the favorable conditions for scholarship and learning in the Roman Empire were upended by political unrest, civil war, urban decay, and looming economic crisis. [89] In around 250 CE, barbarians began attacking and invading the Roman frontiers. These combined events led to a general decline in political and economic conditions. The living standards of the Roman upper class was severely impacted, and their loss of leisure diminished scholarly pursuits. [89] Moreover, during the 3rd and 4th centuries CE, the Roman Empire was administratively divided into two halves: Greek East and Latin West. These administrative divisions weakened the intellectual contact between the two regions. [89] Eventually, both halves went their separate ways, with the Greek East becoming the Byzantine Empire. [89] Christianity was also steadily expanding during this time and soon became a major patron of education in the Latin West. Initially, the Christian church adopted some of the reasoning tools of Greek philosophy in the 2nd and 3rd centuries CE to defend its faith against sophisticated opponents. [89] Nevertheless, Greek philosophy received a mixed reception from leaders and adherents of the Christian faith. [89] Some such as Tertullian (c. 155-c. 230 CE) were vehemently opposed to philosophy, denouncing it as heretic. Others such as Augustine of Hippo (354-430 CE) were ambivalent and defended Greek philosophy and science as the best ways to understand the natural world and therefore treated it as a handmaiden (or servant) of religion. [89] Education in the West began its gradual decline, along with the rest of Western Roman Empire, due to invasions by Germanic tribes, civil unrest, and economic collapse. Contact with the classical tradition was lost in specific regions such as Roman Britain and northern Gaul but continued to exist in Rome, northern Italy, southern Gaul, Spain, and North Africa. [89]

In the Middle Ages, the classical learning continued in three major linguistic cultures and civilizations: Greek (the Byzantine Empire), Arabic (the Islamic world), and Latin (Western Europe).

Byzantine Empire Edit

Preservation of Greek heritage Edit

The fall of the Western Roman Empire led to a deterioration of the classical tradition in the western part (or Latin West) of Europe in the 400s. In contrast, the Eastern Roman or Byzantine Empire resisted the barbarian attacks, and preserved and improved the learning. [90]

While the Byzantine Empire still held learning centers such as Constantinople, Alexandria and Antioch, Western Europe's knowledge was concentrated in monasteries until the development of medieval universities in the 12th centuries. The curriculum of monastic schools included the study of the few available ancient texts and of new works on practical subjects like medicine [91] and timekeeping. [92]

In the sixth century in the Byzantine Empire, Isidore of Miletus compiled Archimedes' mathematical works in the Archimedes Palimpsest, where all Archimedes' mathematical contributions were collected and studied.

John Philoponus, another Byzantine scholar, was the first to question Aristotle's teaching of physics, introducing the theory of impetus. [93] [94] The theory of impetus was an auxiliary or secondary theory of Aristotelian dynamics, put forth initially to explain projectile motion against gravity. It is the intellectual precursor to the concepts of inertia, momentum and acceleration in classical mechanics. [95] The works of John Philoponus inspired Galileo Galilei ten centuries later. [96] [97]

The first record of separating conjoined twins took place in the Byzantine Empire in the 900s when the surgeons tried to separate a dead body of a pair of conjoined twins. The result was partly successful as the other twin managed to live for three days. The next recorded case of separating conjoined twins was several centuries later, in 1600s Germany. [98] [99]

Collapse Edit

During the Fall of Constantinople in 1453, a number of Greek scholars fled to North Italy in which they fueled the era later commonly known as the "Renaissance" as they brought with them a great deal of classical learning including an understanding of botany, medicine, and zoology. Byzantium also gave the West important inputs: John Philoponus' criticism of Aristotelian physics, and the works of Dioscorides. [100]

Islamic world Edit

This was the period (8th–14th century CE) of the Islamic Golden Age where commerce thrived, and new ideas and technologies emerged such as the importation of papermaking from China, which made the copying of manuscripts inexpensive.

Translations and Hellenization Edit

The eastward transmission of Greek heritage to Western Asia was a slow and gradual process that spanned over a thousand years, beginning with the Asian conquests of Alexander the Great in 335 BCE to the founding of Islam in the 7th century CE. [6] The birth and expansion of Islam during the 7th century was quickly followed by its Hellenization. Knowledge of Greek conceptions of the world was preserved and absorbed into Islamic theology, law, culture, and commerce, which was aided by the translations of traditional Greek texts and some Syriac intermediary sources into Arabic during the 8th–9th century.

Education and scholarly pursuits Edit

Higher education at a madrasa (or college) was focused on Islamic law and religious science and students had to engage in self-study for everything else. [6] And despite the occasional theological backlash, many Islamic scholars of science were able to conduct their work in relatively tolerant urban centers (e.g., Baghdad and Cairo) and were protected by powerful patrons. [6] They could also travel freely and exchange ideas as there were no political barriers within the unified Islamic state. [6] Islamic science during this time was primarily focused on the correction, extension, articulation, and application of Greek ideas to new problems. [6]

Advancements in mathematics Edit

Most of the achievements by Islamic scholars during this period were in mathematics. [6] Arabic mathematics was a direct descendent of Greek and Indian mathematics. [6] For instance, what is now known as Arabic numerals originally came from India, but Muslim mathematicians made several key refinements to the number system, such as the introduction of decimal point notation. Mathematicians such as Muhammad ibn Musa al-Khwarizmi (c. 780–850) gave his name to the concept of the algorithm, while the term algebra is derived from al-jabr, the beginning of the title of one of his publications. [101] Islamic trigonometry continued from the works of Ptolemy's Almagest and Indian Siddhanta, from which they added trigonometric functions, drew up tables, and applied trignometry to spheres and planes. Many of their engineers, instruments makers, and surveyors contributed books in applied mathematics. It was in astronomy that Islamic mathematicians made their greatest contributions. Al-Battani (c. 858–929) improved the measurements of Hipparchus, preserved in the translation of Ptolemy's Hè Megalè Syntaxis (The great treatise) translated as Almagest. Al-Battani also improved the precision of the measurement of the precession of the Earth's axis. Corrections were made to Ptolemy's geocentric model by al-Battani, Ibn al-Haytham, [102] Averroes and the Maragha astronomers such as Nasir al-Din al-Tusi, Mo'ayyeduddin Urdi and Ibn al-Shatir. [103] [104]

Scholars with geometric skills made significant improvements to the earlier classical texts on light and sight by Euclid, Aristotle, and Ptolemy. [6] The earliest surviving Arabic treatises were written in the 9th century by Abū Ishāq al-Kindī, Qustā ibn Lūqā, and (in fragmentary form) Ahmad ibn Isā. Later in the 11th century, Ibn al-Haytham (known as Alhazen in the West), a mathematician and astronomer, synthesized a new theory of vision based on the works of his predecessors. [6] His new theory included a complete system of geometrical optics, which was set in great detail in his Book of Optics. [6] [105] His book was translated into Latin and was relied upon as a principal source on the science of optics in Europe until the 17th century. [6]

Institutionalization of medicine Edit

The medical sciences were prominently cultivated in the Islamic world. [6] The works of Greek medical theories, especially those of Galen, were translated into Arabic and there was an outpouring of medical texts by Islamic physicians, which were aimed at organizing, elaborating, and disseminating classical medical knowledge. [6] Medical specialties started to emerge, such as those involved in the treatment of eye diseases such as cataracts. Ibn Sina (known as Avicenna in the West, c. 980–1037) was a prolific Persian medical encyclopedist [106] wrote extensively on medicine, [107] [108] with his two most notable works in medicine being the Kitāb al-shifāʾ ("Book of Healing") and The Canon of Medicine, both of which were used as standard medicinal texts in both the Muslim world and in Europe well into the 17th century. Amongst his many contributions are the discovery of the contagious nature of infectious diseases, [107] and the introduction of clinical pharmacology. [109] Institutionalization of medicine was another important achievement in the Islamic world. Although hospitals as an institution for the sick emerged in the Byzantium empire, the model of institutionalized medicine for all social classes was extensive in the Islamic empire and was scattered throughout. In addition to treating patients, physicians could teach apprentice physicians, as well write and do research. The discovery of the pulmonary transit of blood in the human body by Ibn al-Nafis occurred in a hospital setting. [6]

Decline Edit

Islamic science began its decline in the 12th–13th century, before the Renaissance in Europe, due in part to the Christian reconquest of Spain and the Mongol conquests in the East in the 11th–13th century. The Mongols sacked Baghdad, capital of the Abbasid caliphate, in 1258, which ended the Abbasid empire. [6] [110] Nevertheless, many of the conquerors became patrons of the sciences. Hulagu Khan, for example, who led the siege of Baghdad, became a patron of the Maragheh observatory. [6] Islamic astronomy continued to flourish into the 16th century. [6]

Western Europe Edit

By the eleventh century, most of Europe had become Christian stronger monarchies emerged borders were restored technological developments and agricultural innovations were made, increasing the food supply and population. Classical Greek texts were translated from Arabic and Greek into Latin, stimulating scientific discussion in Western Europe. [111]

In classical antiquity, Greek and Roman taboos had meant that dissection was usually banned, but in the Middle Ages medical teachers and students at Bologna began to open human bodies, and Mondino de Luzzi (c. 1275–1326) produced the first known anatomy textbook based on human dissection. [112] [113]

As a result of the Pax Mongolica, Europeans, such as Marco Polo, began to venture further and further east. The written accounts of Polo and his fellow travelers inspired other Western European maritime explorers to search for a direct sea route to Asia, ultimately leading to the Age of Discovery. [114]

Technological advances were also made, such as the early flight of Eilmer of Malmesbury (who had studied Mathematics in 11th century England), [115] and the metallurgical achievements of the Cistercian blast furnace at Laskill. [116] [117]

Medieval universities Edit

An intellectual revitalization of Western Europe started with the birth of medieval universities in the 12th century. These urban institutions grew from the informal scholarly activities of learned friars who visited monasteries, consulted libraries, and conversed with other fellow scholars. [118] A friar who became well-known would attract a following of disciples, giving rise to a brotherhood of scholars (or collegium in Latin). A collegium might travel to a town or request a monastery to host them. However, if the number of scholars within a collegium grew too large, they would opt to settle in a town instead. [118] As the number of collegia within a town grew, the collegia might request that their king grant them a charter that would convert them into a universitas. [118] Many universities were chartered during this period, with the first in Bologna in 1088, followed by Paris in 1150, Oxford in 1167, and Cambridge in 1231. [118] The granting of a charter meant that the medieval universities were partially sovereign and independent from local authorities. [118] Their independence allowed them to conduct themselves and judge their own members based on their own rules. Furthermore, as initially religious institutions, their faculties and students were protected from capital punishment (e.g., gallows). [118] Such independence was a matter of custom, which could, in principle, be revoked by their respective rulers if they felt threatened. Discussions of various subjects or claims at these medieval institutions, no matter how controversial, were done in a formalized way so as to declare such discussions as being within the bounds of a university and therefore protected by the privileges of that institution's sovereignty. [118] A claim could be described as ex cathedra (literally "from the chair", used within the context of teaching) or ex hypothesi (by hypothesis). This meant that the discussions were presented as purely an intellectual exercise that did not require those involved to commit themselves to the truth of a claim or to proselytize. Modern academic concepts and practices such as academic freedom or freedom of inquiry are remnants of these medieval privileges that were tolerated in the past. [118]

The curriculum of these medieval institutions centered on the seven liberal arts, which were aimed at providing beginning students with the skills for reasoning and scholarly language. [118] Students would begin their studies starting with the first three liberal arts or Trivium (grammar, rhetoric, and logic) followed by the next four liberal arts or Quadrivium (arithmetic, geometry, astronomy, and music). [118] [89] Those who completed these requirements and received their baccalaureate (or Bachelor of Arts) had the option to join the higher faculty (law, medicine, or theology), which would confer an LLD for a lawyer, an MD for a physician, or ThD for a theologian. [118] Students who chose to remain in the lower faculty (arts) could work towards a Magister (or Master's) degree and would study three philosophies: metaphysics, ethics, and natural philosophy. [118] Latin translations of Aristotle's works such as De Anima (On the Soul) and the commentaries on them were required readings. As time passed, the lower faculty was allowed to confer its own doctoral degree called the PhD. [118] Many of the Masters were drawn to encyclopedias and had used them as textbooks. But these scholars yearned for the complete original texts of the Ancient Greek philosophers, mathematicians, and physicians such as Aristotle, Euclid, and Galen, which were not available to them at the time. These Ancient Greek texts were to be found in the Byzantine Empire and the Islamic World. [118]

Translations of Greek and Arabic sources Edit

Contact with the Byzantine Empire, [96] and with the Islamic world during the Reconquista and the Crusades, allowed Latin Europe access to scientific Greek and Arabic texts, including the works of Aristotle, Ptolemy, Isidore of Miletus, John Philoponus, Jābir ibn Hayyān, al-Khwarizmi, Alhazen, Avicenna, and Averroes. European scholars had access to the translation programs of Raymond of Toledo, who sponsored the 12th century Toledo School of Translators from Arabic to Latin. Later translators like Michael Scotus would learn Arabic in order to study these texts directly. The European universities aided materially in the translation and propagation of these texts and started a new infrastructure which was needed for scientific communities. In fact, European university put many works about the natural world and the study of nature at the center of its curriculum, [119] with the result that the "medieval university laid far greater emphasis on science than does its modern counterpart and descendent." [120]

At the beginning of the 13th century, there were reasonably accurate Latin translations of the main works of almost all the intellectually crucial ancient authors, allowing a sound transfer of scientific ideas via both the universities and the monasteries. By then, the natural philosophy in these texts began to be extended by scholastics such as Robert Grosseteste, Roger Bacon, Albertus Magnus and Duns Scotus. Precursors of the modern scientific method, influenced by earlier contributions of the Islamic world, can be seen already in Grosseteste's emphasis on mathematics as a way to understand nature, and in the empirical approach admired by Bacon, particularly in his Opus Majus. Pierre Duhem's thesis is that Stephen Tempier – the Bishop of Paris – Condemnation of 1277 led to the study of medieval science as a serious discipline, "but no one in the field any longer endorses his view that modern science started in 1277". [121] However, many scholars agree with Duhem's view that the mid-late Middle Ages saw important scientific developments. [122] [123] [124] [125]

Medieval science Edit

The first half of the 14th century saw much important scientific work, largely within the framework of scholastic commentaries on Aristotle's scientific writings. [126] William of Ockham emphasised the principle of parsimony: natural philosophers should not postulate unnecessary entities, so that motion is not a distinct thing but is only the moving object [127] and an intermediary "sensible species" is not needed to transmit an image of an object to the eye. [128] Scholars such as Jean Buridan and Nicole Oresme started to reinterpret elements of Aristotle's mechanics. In particular, Buridan developed the theory that impetus was the cause of the motion of projectiles, which was a first step towards the modern concept of inertia. [129] The Oxford Calculators began to mathematically analyze the kinematics of motion, making this analysis without considering the causes of motion. [130]

In 1348, the Black Death and other disasters sealed a sudden end to philosophic and scientific development. Yet, the rediscovery of ancient texts was stimulated by the Fall of Constantinople in 1453, when many Byzantine scholars sought refuge in the West. Meanwhile, the introduction of printing was to have great effect on European society. The facilitated dissemination of the printed word democratized learning and allowed ideas such as algebra to propagate more rapidly. These developments paved the way for the Scientific Revolution, where scientific inquiry, halted at the start of the Black Death, resumed. [131] [132]

Revival of learning Edit

The renewal of learning in Europe began with 12th century Scholasticism. The Northern Renaissance showed a decisive shift in focus from Aristotelian natural philosophy to chemistry and the biological sciences (botany, anatomy, and medicine). [133] Thus modern science in Europe was resumed in a period of great upheaval: the Protestant Reformation and Catholic Counter-Reformation the discovery of the Americas by Christopher Columbus the Fall of Constantinople but also the re-discovery of Aristotle during the Scholastic period presaged large social and political changes. Thus, a suitable environment was created in which it became possible to question scientific doctrine, in much the same way that Martin Luther and John Calvin questioned religious doctrine. The works of Ptolemy (astronomy) and Galen (medicine) were found not always to match everyday observations. Work by Vesalius on human cadavers found problems with the Galenic view of anatomy. [134]

Theophrastus' work on rocks, Peri lithōn, remained authoritative for millennia: its interpretation of fossils was not overturned until after the Scientific Revolution.

During the Italian Renaissance, Niccolò Machiavelli established the emphasis of modern political science on direct empirical observation of political institutions and actors. Later, the expansion of the scientific paradigm during the Enlightenment further pushed the study of politics beyond normative determinations. [ citation needed ] In particular, the study of statistics, to study the subjects of the state, has been applied to polling and voting.

In archeology, the 15th and 16th centuries saw the rise of antiquarians in Renaissance Europe who were interested in the collection of artifacts.

Scientific Revolution and birth of New Science Edit

The early modern period is seen as a flowering of the European Renaissance. There was a willingness to question previously held truths and search for new answers resulted in a period of major scientific advancements, now known as the Scientific Revolution, which led to the emergence of a New Science that was more mechanistic in its worldview, more integrated with mathematics, and more reliable and open as its knowledge was based on a newly defined scientific method. [11] [14] [15] [136] The scientific revolution is a convenient boundary between ancient thought and classical physics, and is traditionally held by most historians to have begun in 1543, when the books De humani corporis fabrica (On the Workings of the Human Body) by Andreas Vesalius, and also De Revolutionibus, by the astronomer Nicolaus Copernicus, were first printed. The period culminated with the publication of the Philosophiæ Naturalis Principia Mathematica in 1687 by Isaac Newton, representative of the unprecedented growth of scientific publications throughout Europe.

Other significant scientific advances were made during this time by Galileo Galilei, Edmond Halley, Robert Hooke, Christiaan Huygens, Tycho Brahe, Johannes Kepler, Gottfried Leibniz, and Blaise Pascal. In philosophy, major contributions were made by Francis Bacon, Sir Thomas Browne, René Descartes, Spinoza and Thomas Hobbes. Christiaan Huygens derived the centripetal and centrifugal forces and was the first to transfer mathematical inquiry to describe unobservable physical phenomena. William Gilbert did some of the earliest experiments with electricity and magnetism, establishing that the Earth itself is magnetic.

Heliocentrism Edit

The heliocentric model that was revived by Nicolaus Copernicus. The thesis of Copernicus' book was that the Earth moved around the Sun, a revival of the heliocentric model of the solar system described by Aristarchus of Samos.

Newly defined scientific method Edit

The scientific method was also better developed as the modern way of thinking emphasized experimentation and reason over traditional considerations. Galileo ("Father of Modern Physics") also made use of experiments to validate physical theories, a key element of the scientific method.

Continuation of Scientific Revolution Edit

The Scientific Revolution continued into the Age of Enlightenment, which accelerated the development of modern science.

Planets and orbits Edit

The heliocentric model that was revived by Nicolaus Copernicus was followed by the first known model of planetary motion given by Johannes Kepler in the early 17th century, which proposed that the planets follow elliptical orbits, with the Sun at one focus of the ellipse.

Calculus and Newtonian mechanics Edit

In 1687, Isaac Newton published the Principia Mathematica, detailing two comprehensive and successful physical theories: Newton's laws of motion, which led to classical mechanics and Newton's law of universal gravitation, which describes the fundamental force of gravity.

Emergence of chemistry Edit

A decisive moment came when "chemistry" was distinguished from alchemy by Robert Boyle in his work The Sceptical Chymist, in 1661 although the alchemical tradition continued for some time after his work. Other important steps included the gravimetric experimental practices of medical chemists like William Cullen, Joseph Black, Torbern Bergman and Pierre Macquer and through the work of Antoine Lavoisier ("father of modern chemistry") on oxygen and the law of conservation of mass, which refuted phlogiston theory. Modern chemistry emerged from the sixteenth through the eighteenth centuries through the material practices and theories promoted by alchemy, medicine, manufacturing and mining. [137]

Circulatory system Edit

William Harvey published De Motu Cordis in 1628, which revealed his conclusions based on his extensive studies of vertebrate circulatory systems. He identified the central role of the heart, arteries, and veins in producing blood movement in a circuit, and failed to find any confirmation of Galen's pre-existing notions of heating and cooling functions. [138] The history of early modern biology and medicine is often told through the search for the seat of the soul. [139] Galen in his descriptions of his foundational work in medicine presents the distinctions between arteries, veins, and nerves using the vocabulary of the soul. [140]

Scientific societies and journals Edit

A critical innovation was the creation of permanent scientific societies, and their scholarly journals, which dramatically speeded the diffusion of new ideas. Typical was the founding of the Royal Society in London in 1660. [141] Directly based on the works [142] of Newton, Descartes, Pascal and Leibniz, the way was now clear to the development of modern mathematics, physics and technology by the generation of Benjamin Franklin (1706–1790), Leonhard Euler (1707–1783), Mikhail Lomonosov (1711–1765) and Jean le Rond d'Alembert (1717–1783). Denis Diderot's Encyclopédie, published between 1751 and 1772 brought this new understanding to a wider audience. The impact of this process was not limited to science and technology, but affected philosophy (Immanuel Kant, David Hume), religion (the increasingly significant impact of science upon religion), and society and politics in general (Adam Smith, Voltaire).

Developments in geology Edit

Geology did not undergo systematic restructuring during the Scientific Revolution but instead existed as a cloud of isolated, disconnected ideas about rocks, minerals, and landforms long before it became a coherent science. Robert Hooke formulated a theory of earthquakes, and Nicholas Steno developed the theory of superposition and argued that fossils were the remains of once-living creatures. Beginning with Thomas Burnet's Sacred Theory of the Earth in 1681, natural philosophers began to explore the idea that the Earth had changed over time. Burnet and his contemporaries interpreted Earth's past in terms of events described in the Bible, but their work laid the intellectual foundations for secular interpretations of Earth history.

Post-Scientific Revolution Edit

Bioelectricity Edit

During the late 18th century, the Italian physician Luigi Galvani took an interest in the field of "medical electricity", which emerged in the middle of the 18th century, following the electrical researches and the discovery of the effects of electricity on the human body. [143] Galvani's experiments with bioelectricity has a popular legend which says that Galvani was slowly skinning a frog at a table where he and his wife had been conducting experiments with static electricity by rubbing frog skin. Galvani's assistant touched an exposed sciatic nerve of the frog with a metal scalpel that had picked up a charge. At that moment, they saw sparks and the dead frog's leg kicked as if in life. The observation provided the basis for the new understanding that the impetus behind muscle movement was electrical energy carried by a liquid (ions), and not air or fluid as in earlier balloonist theories. The Galvanis are credited with the discovery of bioelectricity.

Developments in geology Edit

Modern geology, like modern chemistry, gradually evolved during the 18th and early 19th centuries. Benoît de Maillet and the Comte de Buffon saw the Earth as much older than the 6,000 years envisioned by biblical scholars. Jean-Étienne Guettard and Nicolas Desmarest hiked central France and recorded their observations on some of the first geological maps. Aided by chemical experimentation, naturalists such as Scotland's John Walker, [144] Sweden's Torbern Bergman, and Germany's Abraham Werner created comprehensive classification systems for rocks and minerals—a collective achievement that transformed geology into a cutting edge field by the end of the eighteenth century. These early geologists also proposed a generalized interpretations of Earth history that led James Hutton, Georges Cuvier and Alexandre Brongniart, following in the steps of Steno, to argue that layers of rock could be dated by the fossils they contained: a principle first applied to the geology of the Paris Basin. The use of index fossils became a powerful tool for making geological maps, because it allowed geologists to correlate the rocks in one locality with those of similar age in other, distant localities.

Birth of modern economics Edit

The basis for classical economics forms Adam Smith's An Inquiry into the Nature and Causes of the Wealth of Nations, published in 1776. Smith criticized mercantilism, advocating a system of free trade with division of labour. He postulated an "invisible hand" that regulated economic systems made up of actors guided only by self-interest. The "invisible hand" mentioned in a lost page in the middle of a chapter in the middle of the "Wealth of Nations", 1776, advances as Smith's central message. [ clarification needed ] It is played down that this "invisible hand" acts only "frequently" and that it is "no part of his [the individual's] intentions" because competition leads to lower prices by imitating "his" invention. That this "invisible hand" prefers "the support of domestic to foreign industry" is cleansed—often without indication that part of the citation is truncated. [145] The opening passage of the "Wealth" containing Smith's message is never mentioned as it cannot be integrated into modern theory: "Wealth" depends on the division of labour which changes with market volume and on the proportion of productive to Unproductive labor.

Social science Edit

Anthropology can best be understood as an outgrowth of the Age of Enlightenment. It was during this period that Europeans attempted systematically to study human behavior. Traditions of jurisprudence, history, philology and sociology developed during this time and informed the development of the social sciences of which anthropology was a part.

The 19th century saw the birth of science as a profession. William Whewell had coined the term the term scientist in 1833, [146] which soon replaced the older term natural philosopher.

Electricity and magnetism Edit

In physics, the behavior of electricity and magnetism was studied by Giovanni Aldini, Alessandro Volta, Michael Faraday, Georg Ohm, and others. The experiments, theories and discoveries of Michael Faraday, Andre-Marie Ampere, James Clerk Maxwell, and their contemporaries led to the unification of the two phenomena into a single theory of electromagnetism as described by Maxwell's equations. Thermodynamics led to an understanding of heat and the notion of energy was defined.

Discovery of Neptune Edit

In astronomy, the planet Neptune was discovered. Advances in astronomy and in optical systems in the 19th century resulted in the first observation of an asteroid (1 Ceres) in 1801, and the discovery of Neptune in 1846. In 1925, Cecilia Payne-Gaposchkin determined that stars were composed mostly of hydrogen and helium. [147] She was dissuaded by astronomer Henry Norris Russell from publishing this finding in her PhD thesis because of the widely held belief that stars had the same composition as the Earth. [148] However, four years later, in 1929, Henry Norris Russell came to the same conclusion through different reasoning and the discovery was eventually accepted. [148]

Developments in mathematics Edit

In mathematics, the notion of complex numbers finally matured and led to a subsequent analytical theory they also began the use of hypercomplex numbers. Karl Weierstrass and others carried out the arithmetization of analysis for functions of real and complex variables. It also saw rise to new progress in geometry beyond those classical theories of Euclid, after a period of nearly two thousand years. The mathematical science of logic likewise had revolutionary breakthroughs after a similarly long period of stagnation. But the most important step in science at this time were the ideas formulated by the creators of electrical science. Their work changed the face of physics and made possible for new technology to come about such as electric power, electrical telegraphy, the telephone, and radio.

Developments in chemistry Edit

In chemistry, Dmitri Mendeleev, following the atomic theory of John Dalton, created the first periodic table of elements. Other highlights include the discoveries unveiling the nature of atomic structure and matter, simultaneously with chemistry – and of new kinds of radiation. The theory that all matter is made of atoms, which are the smallest constituents of matter that cannot be broken down without losing the basic chemical and physical properties of that matter, was provided by John Dalton in 1803, although the question took a hundred years to settle as proven. Dalton also formulated the law of mass relationships. In 1869, Dmitri Mendeleev composed his periodic table of elements on the basis of Dalton's discoveries. The synthesis of urea by Friedrich Wöhler opened a new research field, organic chemistry, and by the end of the 19th century, scientists were able to synthesize hundreds of organic compounds. The later part of the 19th century saw the exploitation of the Earth's petrochemicals, after the exhaustion of the oil supply from whaling. By the 20th century, systematic production of refined materials provided a ready supply of products which provided not only energy, but also synthetic materials for clothing, medicine, and everyday disposable resources. Application of the techniques of organic chemistry to living organisms resulted in physiological chemistry, the precursor to biochemistry.

Age of the Earth Edit

Over the first half of the 19th century, geologists such as Charles Lyell, Adam Sedgwick, and Roderick Murchison applied the new technique to rocks throughout Europe and eastern North America, setting the stage for more detailed, government-funded mapping projects in later decades. Midway through the 19th century, the focus of geology shifted from description and classification to attempts to understand how the surface of the Earth had changed. The first comprehensive theories of mountain building were proposed during this period, as were the first modern theories of earthquakes and volcanoes. Louis Agassiz and others established the reality of continent-covering ice ages, and "fluvialists" like Andrew Crombie Ramsay argued that river valleys were formed, over millions of years by the rivers that flow through them. After the discovery of radioactivity, radiometric dating methods were developed, starting in the 20th century. Alfred Wegener's theory of "continental drift" was widely dismissed when he proposed it in the 1910s, but new data gathered in the 1950s and 1960s led to the theory of plate tectonics, which provided a plausible mechanism for it. Plate tectonics also provided a unified explanation for a wide range of seemingly unrelated geological phenomena. Since 1970 it has served as the unifying principle in geology.

Evolution and inheritance Edit

Perhaps the most prominent, controversial, and far-reaching theory in all of science has been the theory of evolution by natural selection, which was independently formulated by Charles Darwin and Alfred Wallace. It was described in detail in Darwin's book The Origin of Species, which was published in 1859. In it, Darwin proposed that the features of all living things, including humans, were shaped by natural processes over long periods of time. The theory of evolution in its current form affects almost all areas of biology. [149] Implications of evolution on fields outside of pure science have led to both opposition and support from different parts of society, and profoundly influenced the popular understanding of "man's place in the universe". Separately, Gregor Mendel formulated in the principles of inheritance in 1866, which became the basis of modern genetics.

Germ theory Edit

Another important landmark in medicine and biology were the successful efforts to prove the germ theory of disease. Following this, Louis Pasteur made the first vaccine against rabies, and also made many discoveries in the field of chemistry, including the asymmetry of crystals. In 1847, Hungarian physician Ignác Fülöp Semmelweis dramatically reduced the occurrency of puerperal fever by simply requiring physicians to wash their hands before attending to women in childbirth. This discovery predated the germ theory of disease. However, Semmelweis' findings were not appreciated by his contemporaries and handwashing came into use only with discoveries by British surgeon Joseph Lister, who in 1865 proved the principles of antisepsis. Lister's work was based on the important findings by French biologist Louis Pasteur. Pasteur was able to link microorganisms with disease, revolutionizing medicine. He also devised one of the most important methods in preventive medicine, when in 1880 he produced a vaccine against rabies. Pasteur invented the process of pasteurization, to help prevent the spread of disease through milk and other foods. [150]

Schools of economics Edit

Karl Marx developed an alternative economic theory, called Marxian economics. Marxian economics is based on the labor theory of value and assumes the value of good to be based on the amount of labor required to produce it. Under this axiom, capitalism was based on employers not paying the full value of workers labor to create profit. The Austrian School responded to Marxian economics by viewing entrepreneurship as driving force of economic development. This replaced the labor theory of value by a system of supply and demand.

Founding of psychology Edit

Psychology as a scientific enterprise that was independent from philosophy began in 1879 when Wilhelm Wundt founded the first laboratory dedicated exclusively to psychological research (in Leipzig). Other important early contributors to the field include Hermann Ebbinghaus (a pioneer in memory studies), Ivan Pavlov (who discovered classical conditioning), William James, and Sigmund Freud. Freud's influence has been enormous, though more as cultural icon than a force in scientific psychology.

Modern sociology Edit

Modern sociology emerged in the early 19th century as the academic response to the modernization of the world. Among many early sociologists (e.g., Émile Durkheim), the aim of sociology was in structuralism, understanding the cohesion of social groups, and developing an "antidote" to social disintegration. Max Weber was concerned with the modernization of society through the concept of rationalization, which he believed would trap individuals in an "iron cage" of rational thought. Some sociologists, including Georg Simmel and W. E. B. Du Bois, utilized more microsociological, qualitative analyses. This microlevel approach played an important role in American sociology, with the theories of George Herbert Mead and his student Herbert Blumer resulting in the creation of the symbolic interactionism approach to sociology. In particular, just Auguste Comte, illustrated with his work the transition from a theological to a metaphysical stage and, from this, to a positive stage. Comte took care of the classification of the sciences as well as a transit of humanity towards a situation of progress attributable to a re-examination of nature according to the affirmation of 'sociality' as the basis of the scientifically interpreted society. [151]

Romanticism Edit

The Romantic Movement of the early 19th century reshaped science by opening up new pursuits unexpected in the classical approaches of the Enlightenment. The decline of Romanticism occurred because a new movement, Positivism, began to take hold of the ideals of the intellectuals after 1840 and lasted until about 1880. At the same time, the romantic reaction to the Enlightenment produced thinkers such as Johann Gottfried Herder and later Wilhelm Dilthey whose work formed the basis for the culture concept which is central to the discipline. Traditionally, much of the history of the subject was based on colonial encounters between Western Europe and the rest of the world, and much of 18th- and 19th-century anthropology is now classed as scientific racism. During the late 19th century, battles over the "study of man" took place between those of an "anthropological" persuasion (relying on anthropometrical techniques) and those of an "ethnological" persuasion (looking at cultures and traditions), and these distinctions became part of the later divide between physical anthropology and cultural anthropology, the latter ushered in by the students of Franz Boas.

Science advanced dramatically during the 20th century. There were new and radical developments in the physical and life sciences, building on the progress from the 19th century. [152]

Theory of relativity and quantum mechanics Edit

The beginning of the 20th century brought the start of a revolution in physics. The long-held theories of Newton were shown not to be correct in all circumstances. Beginning in 1900, Max Planck, Albert Einstein, Niels Bohr and others developed quantum theories to explain various anomalous experimental results, by introducing discrete energy levels. Not only did quantum mechanics show that the laws of motion did not hold on small scales, but the theory of general relativity, proposed by Einstein in 1915, showed that the fixed background of spacetime, on which both Newtonian mechanics and special relativity depended, could not exist. In 1925, Werner Heisenberg and Erwin Schrödinger formulated quantum mechanics, which explained the preceding quantum theories. The observation by Edwin Hubble in 1929 that the speed at which galaxies recede positively correlates with their distance, led to the understanding that the universe is expanding, and the formulation of the Big Bang theory by Georges Lemaître. Currently, general relativity and quantum mechanics are inconsistent with each other, and efforts are underway to unify the two.

Big science Edit

In 1938 Otto Hahn and Fritz Strassmann discovered nuclear fission with radiochemical methods, and in 1939 Lise Meitner and Otto Robert Frisch wrote the first theoretical interpretation of the fission process, which was later improved by Niels Bohr and John A. Wheeler. Further developments took place during World War II, which led to the practical application of radar and the development and use of the atomic bomb. Around this time, Chien-Shiung Wu was recruited by the Manhattan Project to help develop a process for separating uranium metal into U-235 and U-238 isotopes by Gaseous diffusion. [153] She was an expert experimentalist in beta decay and weak interaction physics. [154] [155] Wu designed an experiment (see Wu experiment) that enabled theoretical physicists Tsung-Dao Lee and Chen-Ning Yang to disprove the law of parity experimentally, winning them a Nobel Prize in 1957. [154]

Though the process had begun with the invention of the cyclotron by Ernest O. Lawrence in the 1930s, physics in the postwar period entered into a phase of what historians have called "Big Science", requiring massive machines, budgets, and laboratories in order to test their theories and move into new frontiers. The primary patron of physics became state governments, who recognized that the support of "basic" research could often lead to technologies useful to both military and industrial applications.

Big Bang Edit

George Gamow, Ralph Alpher, and Robert Herman had calculated that there should be evidence for a Big Bang in the background temperature of the universe. [156] In 1964, Arno Penzias and Robert Wilson [157] discovered a 3 Kelvin background hiss in their Bell Labs radiotelescope (the Holmdel Horn Antenna), which was evidence for this hypothesis, and formed the basis for a number of results that helped determine the age of the universe.

Space exploration Edit

Supernova SN1987A was observed by astronomers on Earth both visually, and in a triumph for neutrino astronomy, by the solar neutrino detectors at Kamiokande. But the solar neutrino flux was a fraction of its theoretically expected value. This discrepancy forced a change in some values in the standard model for particle physics.

Advancements in genetics Edit

In the early 20th century, the study of heredity became a major investigation after the rediscovery in 1900 of the laws of inheritance developed by Mendel. [158] The 20th century also saw the integration of physics and chemistry, with chemical properties explained as the result of the electronic structure of the atom. Linus Pauling's book on The Nature of the Chemical Bond used the principles of quantum mechanics to deduce bond angles in ever-more complicated molecules. Pauling's work culminated in the physical modelling of DNA, the secret of life (in the words of Francis Crick, 1953). In the same year, the Miller–Urey experiment demonstrated in a simulation of primordial processes, that basic constituents of proteins, simple amino acids, could themselves be built up from simpler molecules, kickstarting decades of research into the chemical origins of life. By 1953, James D. Watson and Francis Crick clarified the basic structure of DNA, the genetic material for expressing life in all its forms, [159] building on the work of Maurice Wilkins and Rosalind Franklin, suggested that the structure of DNA was a double helix. In their famous paper "Molecular structure of Nucleic Acids" [160] In the late 20th century, the possibilities of genetic engineering became practical for the first time, and a massive international effort began in 1990 to map out an entire human genome (the Human Genome Project). The discipline of ecology typically traces its origin to the synthesis of Darwinian evolution and Humboldtian biogeography, in the late 19th and early 20th centuries. Equally important in the rise of ecology, however, were microbiology and soil science—particularly the cycle of life concept, prominent in the work Louis Pasteur and Ferdinand Cohn. The word ecology was coined by Ernst Haeckel, whose particularly holistic view of nature in general (and Darwin's theory in particular) was important in the spread of ecological thinking. In the 1930s, Arthur Tansley and others began developing the field of ecosystem ecology, which combined experimental soil science with physiological concepts of energy and the techniques of field biology.

Neuroscience as a distinct discipline Edit

The understanding of neurons and the nervous system became increasingly precise and molecular during the 20th century. For example, in 1952, Alan Lloyd Hodgkin and Andrew Huxley presented a mathematical model for transmission of electrical signals in neurons of the giant axon of a squid, which they called "action potentials", and how they are initiated and propagated, known as the Hodgkin–Huxley model. In 1961–1962, Richard FitzHugh and J. Nagumo simplified Hodgkin–Huxley, in what is called the FitzHugh–Nagumo model. In 1962, Bernard Katz modeled neurotransmission across the space between neurons known as synapses. Beginning in 1966, Eric Kandel and collaborators examined biochemical changes in neurons associated with learning and memory storage in Aplysia. In 1981 Catherine Morris and Harold Lecar combined these models in the Morris–Lecar model. Such increasingly quantitative work gave rise to numerous biological neuron models and models of neural computation. Neuroscience began to be recognized as a distinct academic discipline in its own right. Eric Kandel and collaborators have cited David Rioch, Francis O. Schmitt, and Stephen Kuffler as having played critical roles in establishing the field. [161]

Plate tectonics Edit

Geologists' embrace of plate tectonics became part of a broadening of the field from a study of rocks into a study of the Earth as a planet. Other elements of this transformation include: geophysical studies of the interior of the Earth, the grouping of geology with meteorology and oceanography as one of the "earth sciences", and comparisons of Earth and the solar system's other rocky planets.

Applications Edit

In terms of applications, a massive amount of new technologies were developed in the 20th century. Technologies such as electricity, the incandescent light bulb, the automobile and the phonograph, first developed at the end of the 19th century, were perfected and universally deployed. The first airplane flight occurred in 1903, and by the end of the century large airplanes such as the Boeing 777 and Airbus A330 flew thousands of miles in a matter of hours. The development of the television and computers caused massive changes in the dissemination of information. Advances in biology also led to large increases in food production, as well as the elimination of diseases such as polio. Computer science, built upon a foundation of theoretical linguistics, discrete mathematics, and electrical engineering, studies the nature and limits of computation. Subfields include computability, computational complexity, database design, computer networking, artificial intelligence, and the design of computer hardware. One area in which advances in computing have contributed to more general scientific development is by facilitating large-scale archiving of scientific data. Contemporary computer science typically distinguishes itself by emphasising mathematical 'theory' in contrast to the practical emphasis of software engineering.

Developments in political science Edit

In political science during the 20th century, the study of ideology, behaviouralism and international relations led to a multitude of 'pol-sci' subdisciplines including rational choice theory, voting theory, game theory (also used in economics), psephology, political geography/geopolitics, political psychology/political sociology, political economy, policy analysis, public administration, comparative political analysis and peace studies/conflict analysis.

Keynesian and new classical economics Edit

In economics, John Maynard Keynes prompted a division between microeconomics and macroeconomics in the 1920s. Under Keynesian economics macroeconomic trends can overwhelm economic choices made by individuals. Governments should promote aggregate demand for goods as a means to encourage economic expansion. Following World War II, Milton Friedman created the concept of monetarism. Monetarism focuses on using the supply and demand of money as a method for controlling economic activity. In the 1970s, monetarism has adapted into supply-side economics which advocates reducing taxes as a means to increase the amount of money available for economic expansion. Other modern schools of economic thought are New Classical economics and New Keynesian economics. New Classical economics was developed in the 1970s, emphasizing solid microeconomics as the basis for macroeconomic growth. New Keynesian economics was created partially in response to New Classical economics, and deals with how inefficiencies in the market create a need for control by a central bank or government.

Developments in psychology, sociology, and anthropology Edit

Psychology in the 20th century saw a rejection of Freud's theories as being too unscientific, and a reaction against Edward Titchener's atomistic approach of the mind. This led to the formulation of behaviorism by John B. Watson, which was popularized by B.F. Skinner. Behaviorism proposed epistemologically limiting psychological study to overt behavior, since that could be reliably measured. Scientific knowledge of the "mind" was considered too metaphysical, hence impossible to achieve. The final decades of the 20th century have seen the rise of cognitive science, which considers the mind as once again a subject for investigation, using the tools of psychology, linguistics, computer science, philosophy, and neurobiology. New methods of visualizing the activity of the brain, such as PET scans and CAT scans, began to exert their influence as well, leading some researchers to investigate the mind by investigating the brain, rather than cognition. These new forms of investigation assume that a wide understanding of the human mind is possible, and that such an understanding may be applied to other research domains, such as artificial intelligence. Evolutionary theory was applied to behavior and introduced to anthropology and psychology through the works of cultural anthropologist Napoleon Chagnon and E.O. Wilson. Wilson's book Sociobiology: The New Synthesis discussed how evolutionary mechanisms shaped the behaviors of all living organisms, including humans. Decades later, John Tooby and Leda Cosmides would develop the discipline of evolutionary psychology.

American sociology in the 1940s and 1950s was dominated largely by Talcott Parsons, who argued that aspects of society that promoted structural integration were therefore "functional". This structural functionalism approach was questioned in the 1960s, when sociologists came to see this approach as merely a justification for inequalities present in the status quo. In reaction, conflict theory was developed, which was based in part on the philosophies of Karl Marx. Conflict theorists saw society as an arena in which different groups compete for control over resources. Symbolic interactionism also came to be regarded as central to sociological thinking. Erving Goffman saw social interactions as a stage performance, with individuals preparing "backstage" and attempting to control their audience through impression management. While these theories are currently prominent in sociological thought, other approaches exist, including feminist theory, post-structuralism, rational choice theory, and postmodernism.

In the mid-20th century, much of the methodologies of earlier anthropological and ethnographical study were reevaluated with an eye towards research ethics, while at the same time the scope of investigation has broadened far beyond the traditional study of "primitive cultures".

Higgs boson Edit

On July 4, 2012, physicists working at CERN's Large Hadron Collider announced that they had discovered a new subatomic particle greatly resembling the Higgs boson, a potential key to an understanding of why elementary particles have mass and indeed to the existence of diversity and life in the universe. [162] For now, some physicists are calling it a "Higgslike" particle. [162] Peter Higgs was one of six physicists, working in three independent groups, who, in 1964, invented the notion of the Higgs field ("cosmic molasses"). The others were Tom Kibble of Imperial College, London Carl Hagen of the University of Rochester Gerald Guralnik of Brown University and François Englert and Robert Brout, both of Université libre de Bruxelles. [162]


The History of Science in Ancient Greece

It’s true that the Ancient Greeks were curious about the world in which they lived. It is this curiosity that led them to make many advancements to intellectual thought.This included disciplines like philosophy, mathematics, astronomy, and the sciences. In fact, many of the discoveries that resulted from their curiosity led to the further development of these disciplines.

Tracing the history of science in Ancient Greece can be a slight challenge. People such as Archimedes, Pythagoras, Anaximedes, Hippocrates, Aristotle, Heraclitus, Anaximander and Thales of Miletusall contributed to the wealth of scientific studies and innovations that spawned many of today’s inventions and theories.

However, many of the historical figures who were involved with some of the major discovers also worked in other disciplines. For example, Aristotle was both a philosopher and scientist, and Pythagoras made important contributions to mathematics.

Here’s more information about some of the historical figures that made significant contributions to science in Ancient Greece:

Astronomy

Thales of Miletus is credited with being the “Father of Science.” Although he was born in Miletus, Turkey in 620, B.C., he endowed science history with investigations into basic principles and questioned “originating substances of matter.”

He also proposed theories that explained many events of nature, support of the earth, causes of change and the primary substance. His interest in the heavens led to the beginning of Greek explorationof astronomy.

General Science

Science in Ancient Greek history was mainly based upon mathematics, philosophy and logical thinking, along with early technology and everyday existence. Eratosthenes of Alexandria wrote many treatises on geography and astronomy and is given credits in both disciplines. He is given credit for being the first to measure the earth’s circumference.

One of Aristotle’s students, Theophrastus, is known as the “Father of Botany.” He penned a work along with Aristotle where he gave plants names and classified them. He also wrote works that were based on signs of weather, winds, fire, sensations, scents and other varied subjects of scientific interest.

Medicine

Hippocrates is perhaps the most well-known for his scientific advancements in medicine. In ancient Greece, he was known mainly as a physician in the Age of Pericles and for his contributions to biomedical methodology. He is also known for his directive on codes of professional ethics which physicians today recognize as the “Hippocratic Oath.” He is often referred to as the Father of Modern Medicine because of his contributions.

The contributions the Ancient Greeks made to the sciences were vast, and this was only a brief overview. The bottom line is that the Greeks were committed to finding real answers to questions that they asked concerning how the world worked. They could have easily turned to religion and created stories to find answers, but instead the Greeks were committed to knowing the truth. For more information about science in Ancient Greece, watch this episode of the show, The Greek Guide to Greatness.

Related Posts

It is well known that the ancient Greeks, particularly the ancient Athenians, developed the concept&hellip

On October 28 of each year citizens of Greece and Cyprus, as well as Greek&hellip

Rebetiko is a form of urban Greek music which came about in the late 19th&hellip


Classical Greek Geometry - 1

Greek science and mathematics is distinguished from that of earlier cultures by its desire to know, in contrast to a need to make purely utilitarian advances or improvements. Greek geometry displays abstract and deductive elements which were largely lost during the Dark Ages, following the collapse of the Roman Empire, and only gradually recovered in the 16th and 17th centuries. It must be understood that many of the great discoveries in geometry were made about two and half thousand years ago. Given the difficulty of preserving fragile manuscripts, written on parchment or papyrus, over centuries when warfare could wipe out civilizations, it is not too surprising to find that we do not have many reliable records about the origin of Greek geometry or of its practitioners. We may count ourselves lucky that a few commentaries on Greek geometry, written in the fourth or fifth centuries of the present era, have survived to provide us with what details we have.

We cannot give a systematic account of how Greek geometry came into existence and how it was perfected, so we must confine ourselves to describing a few generally agreed highlights. Thales (c. 624-546 BCE) is considered to be the founder of Greek geometry. He was born in Miletus, a town now in modern Turkey (Asia Minor). He was also an astronomer and philosopher. He was held in high regard by the ancient Greeks, and named as one of the seven ‘wise men’ of Greece. He is said to have made a prediction of a solar eclipse which, according to the famous historian Herodotus, occurred during a battle of the Medes and the Lydians. Modern astronomers have dated this eclipse to 28 May, 585 BCE, which serves to give us some idea of the dates of Thales. While it is doubted if someone could have predicted an eclipse so accurately at the given date, the story of its happening assured his fame.

Various stories about Thales have come down to us from historians. One story relates that he travelled to Egypt, where he became acquainted with Egyptian geometry. While the Egyptian approach to geometry was essentially practical, Thales’s work was the start of an abstract investigation of geometry. The following discoveries of elementary geometry are attributed to Thales.

• A circle is bisected by any of its diameters.

• The angles at the base of an isosceles triangle are equal.

• When two straight lines cut each other, the vertically opposite angles are equal.

• The angle in a semicircle is a right angle.

• Two triangles are equal in all respects if they have two angles and one side respectively equal.

He is also credited with a method for finding the distance to a ship at sea, and a method to determine the height of a pyramid by means of the length of its shadow. It is not certain whether this implies that he understood the theory of similar (equiangular) triangles.

Thales may be considered to have originated the geometry of lines, which forms a basic part of elementary geometry. It seems that he passed on no written work to later generations, so we must rely on traditional stories, not all likely to be true, for our information about him.

The commentator Proclus (whom we will discuss in more detail later), writing almost one thousand years after the time in which Thales flourished, says that Thales first brought knowledge of geometry into Greece after his time spent in Egypt. With regard to the state of Egyptian geometry, Herodotus believed that basic knowledge of geometry originated from the recurrent need to measure land after inundation by the Nile. Aristotle, on the other hand, believed that mathematics was the invention of Egyptian priests with the time and leisure to speculate on abstract things. There is controversy among modern historians of mathematics about the extent of Thales’s discoveries. It is first noted that Egyptian geometry was rudimentary, had no theoretical basis, and consisted mainly of a few techniques of mensuration. It is also considered unlikely that Thales could have obtained theoretical proofs of the theorems attributed to him, but he may guessed the truth of the results on the basis of measurements in particular cases.

The next major figure in the history of Greek geometry is Pythagoras. He is thought to have been born around 582 BCE, in Samos, one of the Greek islands. He had a reputation of being a highly learned man, a reputation that endured for many centuries. He is said to have visited Egypt and possibly Babylon, where he may have learnt astronomical and mathematical information, as well as religious lore. He emigrated around 529 BCE to Croton in the south of Italy, where a Greek colony had earlier been founded. He became the leader there of a quasi-religious brotherhood, who aimed to improve the moral basis of society. After opposition developed to the influence of his followers, he moved to Metapontum, also in the south of Italy, where he is thought to have died around 500.

While geometry was introduced to Greece by Thales, Pythagoras is held to be the first to establish geometry as a true science. It is difficult to distinguish the work of the followers of Pythagoras (the Pythagoreans, as they are called) from that of Pythagoras himself, and the Pythagoreans published none of their work. Thus it is not possible to ascribe accurately any given work to Pythagoras himself.

A number of statements regarding the Pythagoreans have been transmitted to us, among which are the following.

• Aristotle says “the Pythagoreans first applied themselves to mathematics, a science which they improved and penetrated with it, they fancied that the principles of mathematics were the principles of all things.”

• Eudemus, a pupil of Aristotle, and a writer of a now lost history of mathematics, states that “Pythagoras changed geometry into the form of a liberal science, regarding its principles in a purely abstract manner, and investigated its theorems from the immaterial and intellectual point of view.”

• Aristoxenus, who was a musical theorist, claimed that Pythagoras esteemed arithmetic above everything else. (“All is number” is a motto attributed to Pythagoras.)

• Pythagoras is said to have discovered the numerical relations of the musical scale.

• Proclus says that “the word ‘mathematics’ originated with the Pythagoreans.” (The word ‘mathematics’ means ‘that which is learned’, with connotations of knowledge and skill.)

Concerning the geometric work of the Pythagoreans we have the following testimony.

• Eudemus states that the theorem that the sum of the angles in a triangle is two right angles is due to the Pythagoreans and their proof is similar to that given in Book 1 of Euclid’s Elements.

• According to Proclus, they showed that space may be uniformly tesselated by equilateral triangles, squares, or regular hexagons.

• Eudemus states that the Pythagoreans discovered the five regular solids.

• Heron of Alexandria and Proclus ascribe to Pythagoras a method of constructing right–angled triangles whose sides have integer length.

• Eudemus ascribes the discovery of irrational quantities to Pythagoras.

We should now address some of the issues that arise from these claims, as they are not accepted by all commentators and, indeed, some are implausible. The theorem that the sum of the angles in a triangle is two right angles is not provable without recourse to Euclid’s fifth or parallel postulate. This is a highly subtle point and any proof by the Pythagoreans that the sum is constant must have had some implied appeal to the parallel postulate. The Greek historian Plutarch tells us that the Egyptians knew of the right-angled triangle whose sides have lengths equal to 3, 4, and 5 units, and that in this case they observed that the square of the hypotenuse equals the sum of the squares of the other two sides. Other versions of this arithmetical construction seem to have been known earlier in Babylon. More generally, positive integers a, b and c are said to form a Pythagorean triple (a, b, c) if a 2 + b 2 = c 2 . It seems to have become known at some time that such Pythagorean triples may be used to form the sides of a right angled triangle, where the hypotenuse has length c units, and so on. Proclus has described a method of finding such Pythagorean triangles using an odd integer m, which he attributes to Pythagoras. We take an odd integer m and set

Note that both b and c are integers, because m is odd. It is straightforward to verify that (a, b, c) is a Pythagorean triple, and this is the method used by Pythagoras to generate such triples. There seems to be agreement that what we know as the theorem of Pythagoras concerning right-angled triangles is not due to Pythagoras or the Pythagoreans. A proof of the general theorem is found as Proposition 47 in Book 1 of Euclid’s Elements, but is more complicated than the proof that would be given nowadays, using the theory of similar triangles.

We will have more to say about the five regular or Platonic solids later in this chapter. Suffice it to say here that the five regular solids are the tetrahedron, cube, octahedron, dodecahedron and icosahedron. The regular tetrahedron, cube, octahedron are of ancient origin and may be seen in Egyptian architecture. Thus it cannot be said that the Pythagoreans discovered these solids. Specialists now agree that it is unlikely that the Pythagoreans discovered the other two regular solids, the dodecahedron and icosahedron,

whose constructions are less obvious. Instead, it seems that Theaetetus, an Athenian who died in 369 BCE, discovered the other two regular solids and wrote a study of all five solids. It is possible that he proved that only five different types of regular solid exist (this is a theorem in Euclid’s Elements). Theaetetus was associated with Plato and his Academy in Athens, and his death was commemorated by Plato’s dialogue entitled Theaetetus. This dialogue also contains information on irrational numbers, which had recently been discovered and had caused a furore in mathematical and philosophical circles of the time. Theaetetus was associated with some of this work on irrationals. The regular solids are also called Platonic solids, because of the importance they held in the teaching of Plato. He used the solids to explain various scientific phenomena. Indeed, the four elements (earth, air, fire and water) were associated with the five regular solids in a cosmic scheme that fascinated thinkers well into Renaissance times.

Concerning irrational quantities, we encounter some problems about the Greek concepts of magnitude and number. Magnitudes are what we would call continuous quantities, such as lengths of lines or areas of plane figures. Number is a discrete quantity, such as an integer. Aristotle made a distinction between these two quantities. A magnitude is that which is divisible into divisibles that are infinitely divisible, while the basis of number is the indivisible unit. The Pythagoreans did not make such a distinction, as they considered number to be the basis of everything and believed that everything can be counted. To count a length, one needed a unit of measure. Once this unit was chosen, it was indivisible. They then assumed that it is possible to choose a unit so that the diagonal and side of a square can both be counted. This was eventually shown to be untrue–the precise time is uncertain. As was said in Greek mathematics, the lengths of the diagonal and the side of a square are incommensurable–they do not possess a common unit of measure. Nowadays we would say that, in its initial stages, the Greek theory of numbers essentially held that all numbers are rational. The consensus now is that the discovery of incommensurable magnitudes, or equivalently, of irrational quantities, is not due to Pythagoras or the group associated with him, but to later Pythagoreans, around 420 BCE.

The modern approach to the question is quite straightforward. Suppose that we have a unit square. Then by the Pythagoras theorem, if c is the length of the diagonal, c 2 = 2. Now we claim that c cannot be a rational number, that is, it cannot be expressed as a quotient of two integers. For suppose thatwhere r and s are integers. We can

assume that r and s have no common factors. Then, on squaring, we obtain

Since 2s 2 is an even integer, r 2 is even and thus r is even. Thus we can write r = 2t, where t is an integer. Substituting, we obtain s 2 = 2t 2 , and hence s is also even. This contradicts the assumption that r and s have no common factor. Rather similar arguments can be used to prove that several other square roots of integers are irrational. This was already known in the circles around Plato. Indeed, in his dialogue Theaetetus, Plato says that his teacher, Theodorus of Cyrene, also the teacher of Theaetetus, had proved that the square root of any non-square integer between 3 and 17 is irrational. From the modern point of view, this is easy to prove, as the the square root of any non-square integer is irrational. Presumably the method used by Theodorus involved specific arguments that missed the full mathematical generality.

The personality and thought of Plato play a large role in the history of Greek mathematics, so we should say something about his life and influence. Plato (427-347 BCE) is known primarily as a philosopher but he was an important promoter of mathematics, especially geometry. He founded the famous Academy in Athens, around 380 BCE, which became a centre where specialists met and discussed intellectual topics. Innovative mathematicians, including Theodorus of Cyrene, Eudoxus of Cnidus, Theaetetus and Menaechmus, are closely associated with the Academy. Plato himself made no significant contribution to creative mathematics, but he inspired others to ground-breaking work and guided their activity. It is said that over the doors of his school the motto “Let no one ignorant of geometry enter” was written. The authenticity of this claim is doubtful, as the earliest reference to it occurs in the sixth century CE, but nonetheless it encapsulates the spirit of his Academy.

We know much detail about Plato’s life and career, and virtually all his writings have survived. The source for much of our information about Plato, and indeed about many other philosophers, is “Lives of the Philosophers” by Diogenes Laertius (3rd century CE?). Diogenes has been described as a mere compiler and anecdote-monger, and his testimony cannot always be trusted, but he seems to be reliable on many aspects relating to Plato (he provides, for example, Plato’s will).

Plato became associated with Socrates, close to the trial and execution of the latter for impiety in 399. Plato was impressed by Socrates’s use of the art of argument and his

search for truth, but we should note that Socrates was himself no enthusiast for mathematics. Plato felt that it was his duty to defend Socratic ideas and methods, and conceived the notion of training the young men of Athens in the discipline of mathematics and then, when mentally ready, in Socratic interrogation. This was to counteract what he saw as the problem of young people bewildering themselves in philosophical enquiry at too early an age.

Around the year 390, Plato visited Sicily, where he came under the influence of Archytas of Tarentum, a follower of the Pythagoreans. Archytas studied, among other mathematical topics, the theory of those means that are associated with Greek mathematics: the arithmetic, geometric and harmonic means. Plato returned to Athens in 388, and in the next twenty years, his Academy came into existence. The purpose of the Academy was to train young people in the sciences (mathematics, music and astronomy) before they undertook careers as legislators and administrators. The two main interests of the Academy were mathematics and dialectic (the Socratic examination of the assumptions made in reasoning). While Plato regarded the study of mathematics as preparatory to the study of dialectic, he nonetheless believed that the study of arithmetic and plane geometry, as well as the geometry of solids, must form the basis of an education leading to knowledge, as opposed to opinion. Plato’s teaching at the Academy was assisted by Theaetetus, whom we have mentioned above. Eudoxus of Cnidus, a pupil of Archytas and an important contributor to the emerging Greek theory of magnitude and number, also taught from time to time at the Academy. Plato’s role in the teaching at the Academy was probably that of an organizer and systematizer, and he may have left the specialist teaching to others. The Academy may be seen as a place where selected sciences were taught and their foundations examined as a mental discipline, the goal being practical wisdom and legislative skill. Clearly, this has relevance to the nature of university learning nowadays, especially as it relates to the conflict between a liberal education, as espoused by Plato, and vocational education with some special aim or skill in mind.

Plato’s enthusiasm for mathematics is described by Eudemus, writing some time after the death of Plato:

• Plato . . .caused the other branches of knowledge to make a very great advance through his earnest zeal about them, and especially geometry: it is very remarkable how he crams his essays throughout with mathematical terms and illustrations, and everywhere tries to arouse an admiration for them in those who embrace the study

Aristotle (384-322 BCE), the famous philosopher and logician, came to Athens in 367 and became a member of Plato’s Academy. He remained there for twenty years, until Plato’s death in 347. As we noted above, in Plato’s time, dialectic was of primary importance at the Academy, with mathematics an important prerequisite. Aristotle held that the mathematical method then being developed was to be a model for any properly organized science. Greek mathematics at the time was distinguished by its axiomatic method, and sequence of reasoning, from which irrefutable theorems are derived. Aristotle required that any science should proceed as mathematics does, and the mathematical method should be applied to all sciences.

Aristotle is important for laying down the working method for each demonstrative science. Writing in his Posterior Analytics, he says:

• By first principles in each genus I mean those the truth of which it is not possible to prove. What is denoted by the first terms and those derived from them is assumed but, as regards their existence, this must be assumed for the principles but proved for the rest. Thus what a unit is, what the straight line is, or what a triangle is must be assumed, but the rest must be proved. Now of the premises used in demonstrative sciences some are peculiar to each science and others are common to all . . .Now the things peculiar to the science, the existence of which must be assumed, are the things with reference to which the science investigates the essential attributes, e.g. arithmetic with reference to units, and geometry with reference to points and lines. With these things it is assumed that they exist and that they are of such and such a nature. But with regard to their essential properties, what is assumed is only the meaning of each term employed: thus arithmetic assumes the answer to the question what is meant by ‘odd’ or ‘even’, ‘a square’ or ‘a cube’, and geometry to the question what is meant by ‘the irrational’ or ‘deflection’ or the so-called ‘verging’ to a point.

Aristotle notes that every demonstrative science must proceed from indemonstrable principles otherwise, the steps of demonstration would be endless. This is especially apparent in mathematics. He discusses the nature of what is an axiom, a definition, a postulate and a hypothesis. It is quite difficult to distinguish between a postulate and a hypothesis. All these terms play a leading role in Euclid’s Elements.

Aristotle’s influence on later European thought was immense. For many centuries,

virtually all Greek learning, except that of Aristotle, fell into oblivion. Aristotle was held to be the basis of all knowledge. Universities and grammar schools were founded with the study of Aristotle as their main intellectual activity. We see the extent of his influence even now by noting how many Aristotelian words have survived in modern use, for example: principle, maxim, matter, form, energy, quintessence, category, and so on. It was really only in the Renaissance that the authority of Aristotle was questioned and supplanted.

We have little reliable knowledge about the lives of the early Greek geometers, and our best sources are the Alexandrian mathematician Pappus (exact dates unknown, probably third century CE) and the Byzantine Greek mathematician Proclus (410-485 CE), who both lived many centuries after the golden age of Greek geometry had ended. Proclus, who wrote a commentary on the first book of Euclid’s Elements, is our main authority on Euclid. He states that Euclid lived in the time of Ptolemy I, king of Egypt, who reigned 323-285 BCE, and that Euclid was younger than the associates of Plato (active around 350 BCE) but older than Eratosthenes (276-196 BCE) and Archimedes (287-212 BCE). Euclid is said to have founded the school of mathematics in Alexandria, a city that was becoming a centre of commerce, and of learning, following its foundation around 330 BCE. Proclus has preserved a famous incident relating to Euclid. On being asked by Ptolemy whether he might learn geometry more easily than by studying the Elements, Euclid replied that “there is no royal road to geometry”. The exact dates of Euclid, his place of birth, and details of his life are not known, but we can say that he flourished around 300 BCE.


4. Earliest Practice of Medicine

The ancient world did not fare too well when it came to the curing of disease. Back then, diseases were supposed to be the gods’ way of punishing humans and all possible remedies were surrounded by superstition. That all changed when Hippocrates of Cos started to collect data and conduct experiments to show that disease was a natural process that the signs and symptoms of a disease were caused by the natural reactions of the body to the disease process. Born in 460 BC, Hippocrates was an ancient Greek physician of the Classical age and was considered one of the most outstanding figures in the history of medicine. He was referred to as the father of Western medicine in recognition of his lasting contributions to the field and was the founder of the Hippocratic School of Medicine.

The most famous of his contributions is the Hippocratic Oath, which bears his name. It was this document that first proposed an ethical standard among doctors. It covers many important concepts which are still used today such as doctor–patient confidentiality.


Hippocrates

Hippocrates was a Greek doctor who made many contributions to medicine. He founded the first school of medicine, which was the first place where medicine was separated from philosophy and religion. Instead of believing that illness happened as a punishment from the gods, Hippocrates suggested that people got sick because of how or where they lived. Although Hippocrates did not understand a lot about anatomy and physiology, he believed in the importance of careful attention and technique as doctors treated their patients.


Watch the video: ΤΟ ΘΑΥΜΑ ΤΩΝ ΕΛΛΗΝΩΝ, ΕΛΛ. ΥΠΟΤΙΤΛΟΙ La légende des sciences