In dealing with the natural world, whether it be the universe, material objects such as earth and water, plants, animals or human beings themselves, the Greeks assumed, as a starting point, that there was an underlying order to all things. Their self-imposed task was to find out what this was for each discipline. In astronomy the Greeks made three assumptions: that the earth was at the centre of the universe, that the stars moved around it in a regular way, and that their movement was circular. In medicine the Greeks admitted that it was difficult to find a fundamental principle behind the working of so complex an organism as the human body, but they nevertheless began from the premise that the body (like the ideal city) tended towards eunomie—in this context, good health—and so illness suggested some aberration in the normal working of things. (The greatest physician of all, Galen, did attempt to base medical knowledge on incontrovertible, geometrical-style proofs but understandably ran into philosophical difficulties.) 16 These assumptions were only a starting point. There had then to be the gathering of empirical evidence, observations of the stars or the working of the body, so that explanations could be made. There were immense difficulties in this. Herodotus could never have reached the source of the Nile. In astronomy one had only the naked eye with which to observe the universe and rudimentary methods of preserving accurate recordings over time, although matters were helped when the findings from many centuries of observation by the Babylonians reached the Greek world in the third century B.C. Similarly in medicine, much could not be observed because a living body’s internal organs could not be seen functioning.
What is remarkable is how much the Greeks did achieve. In astronomy, for instance, of their three assumptions about the universe, one was false (that the sun revolves around the earth), but they were right in seeing a predictable pattern of behaviour in the stars, which for the planets at least was circular. Observations of the shadow of the earth on the moon convinced the Greeks that it was a sphere,17 and their assumption that the earth was at the centre of the universe was not based on ignorance or lazy thinking but was established after serious examination of the alternatives. If the earth was moving around the sun (as Aristarchus hypothesized early in the third century B.C.), then surely its relationship with the stars would change more radically over time. (The Greeks could not conceive that the stars were as far from the earth as they really are.) If the earth spun on its axis (as Heracleides of Pontus proposed in the fourth century), why were the clouds, which could be assumed to be stationary in relationship to the moving earth, not seen to be “left behind” as it spun round? Both reason and experience seemed to confirm the Greek view of an earth-centred universe. In time, of course, science would challenge this “common sense” perception of things.
Perhaps the most impressive feature of Greek astronomy is its ingenuity. It was clear that some stars did not appear to follow a regular course. They were termed planetes, the wanderers. Sophisticated attempts were made to give them regular movements that comprehended their observed wanderings in line with the assumption that their movement was circular. One hypothesis was that each planet moved around the circumference of a circle whose own centre was moving in a circle around the earth. As more records were made, such hypotheses became more and more elaborate, the most sophisticated being those of Ptolemy in the second century A.D. They were, of course, erroneous because the original assumption that the planets revolve around the earth was wrong. However, had the Greek intellectual tradition survived, it is easy to imagine that someone in ancient times might have taken the mass of observations, applied them to Aristarchus’ hypothesis that the sun was the centre of the solar system and the conclusion—that the earth and the planets revolve around the sun—would have fallen elegantly into place, as it did for Copernicus many centuries later. The very elegance of the solution would have, to the Greeks, confirmed that it was likely to be correct. In line with much of Greek thinking, the view that the earth was the centre of the universe remained an assumption, not an article of faith.
Greek astronomy was not confined to the observation of the planets and their motions. It was the combination of these observations with sophisticated mathematical calculation that was truly impressive. One of the most remarkable achievements of Greek astronomy was Hipparchus’ definition of the precession of the equinoxes in the second half of the second century B.C. As the earth is not an exact sphere its axes oscillate slightly. This oscillation causes a consistent shift in its position as a viewing platform, but the shift is so slight that it takes nearly 26,000 years, at a rate of roughly a degree every seventy years, for the earth to complete a circuit back to its original position. Using the naked eye, earlier observations from Babylonia and his own instruments for marking the position of the stars, Hipparchus noted the tiny shift, and his calculation of it as a degree every hundred years was remarkably accurate considering the primitive nature of his technology. Aristarchus calculated the relative sizes and distances of the sun and the moon by observing the full and half moons in relation to the sun, and Eratosthenes’ calculation of the circumference of the earth was possibly within 200 miles (320 kilometres) of the true figure. In all these cases mathematics, including for the first time trigonometry, was being put to practical use by being combined with meticulous observation. 18
Astronomy provides only one example of the Greeks’ search for “the truth.” Their concerns spread to every aspect of knowledge. It is in the nature of man, according to Aristotle, to be curious. Aristotle (384–322 B.C.) arrived in Athens from the northern Aegean (his father had been court physician to the king of Macedon and legend records that he himself was later tutor to Alexander “the Great”). His Macedonian connections made him vulnerable in Athens (for reasons which will become clear in chapter 4), and he travelled widely. He is found probing into every area of intellectual activity, exploring the ultimate nature of things, the ends of human life, the best form of government, the variety of animal life, the importance of tragedy, the nature of rhetoric, the problems of logic. His method was to master what had been said on any subject before, freely criticizing ideas he found inadequate and isolating the questions that needed to be answered. He would move forward himself only after accumulating as much empirical evidence as he could. So his work on zoology included studies of animal life that ranged from the European bison to the mite and from octopuses to oysters. When he was working out his views on the best form of government, he assembled details of 158 Greek constitutions. He speculated more profoundly than anyone before him on the nature of living organisms, exploring their essence, the essential features which made each distinct from other species, and the purpose of each species, which, in Aristotle’s philosophy, was central to its identity. 19
While Aristotle believed that an underlying unity would be found to all knowledge, he accepted that in the present state of knowledge much must remain provisional and unsure. Take, for example, a difficult question in the natural world, how to differentiate between “plants” and “animals.” A dogmatic scientist might have drawn up some arbitrary rules and simply classified each organism as one or the other. Aristotle realized that this was to avoid the real issue. He took some examples from the marine world, the sponge, the jellyfish, sea anemones, razor shells. He noted that when a sponge was pulled from a rock to which it was attached, it reacted by clinging to the rock. So perhaps it was some kind of animal. Yet it could not live detached from a rock, as an animal would. Jellyfish, on the other hand, lived as detached organisms but did not, so far as Aristotle could see, have any perception. They are like plants but, unlike other plants, do not stay attached to a base. Should one create a separate category, “plants which are detached,” or does one accept that it is possible to be an animal without having perception? Aristotle’s genius lay in realizing that these issues had to be worked out undogmatically, that observation had to continue and that sometimes the boundaries between categories would have to be redrawn as a result. In the natural world one could seldom, perhaps never, talk
with absolute certainty in the face of the mass of living organisms that had to be categorized. It was this openness to the provisional nature of knowledge that helps make Aristotle one of the truly great philosophers.20
Aristotle also firmly believed that knowledge would be cumulative from generation to generation, and this process was supported by the competitive nature of Greek science. Take, for example, the idea of spontaneous generation. Aristotle first posited the concept after he had tried in vain to find out how eels spawned. He could find elvers, young eels, but no sign of what they grew from. The answer was straightforward if remarkable—eels spawned in the Bermudas and the young swam back to Europe—but, of course, this was well beyond any possibility of discovery in the fourth century B.C. The act of spawning was not observed for the first time until the 1920s. So the idea of spontaneous generation, from mud in the case of eels, was one possibility. Aristotle’s successor Theophrastus took the matter further. He examined many different cases of apparent spontaneous generation in plants and showed that, in fact, there were often tiny seeds from which plants grew. He noted too that spontaneous generation seemed to take place when earth was warmed. Even though he could not grasp the importance of this as we can today, he still recorded it as part of his investigation. He concluded by leaving the issue open: “More accurate investigation must be made of the subject and the matter in which spontaneous generation takes place be thoroughly inquired into . . . This is why an experienced person is needed to gather it [the evidence], who has the ability to observe the proper season and recognise the seed itself.” For Theophrastus it remained a possibility that every form of apparently spontaneous generation would one day be explained, although he insisted that the concept remain in place until it was actually disproved by empirical observation. He was also insistent on the importance of professional expertise, another important development in the history of science.21
Crucially, Theophrastus was not prepared to accept the views of even such a great scientist as Aristotle (who also happened to be an associate of his) uncritically. He actively sought out explanations (the tiny seeds) that might undermine Aristotle’s suggestion. This was fundamental to the nature of Greek science. It was essentially competitive, with each scientist not only building on earlier observations but seeking to outdo his predecessors. Geoffrey Lloyd sums up its distinctive nature:
The extant remains of Egyptian and Babylonian medicine, mathematics and astronomy can be combed in vain for a single example of a text where an individual author explicitly distances himself from, and criticises, the received tradition in order to claim originality for himself, whereas our Greek sources repeatedly do that.22
Lloyd gives a wide range of examples from medical treatises where an author explains what he believes, the observations on which the belief is based and why it differs from what has been believed before. Anyone, even an Aristotle, could be challenged by anyone who comes after. There can be certainty, in mathematics for instance, but this is based on postulates on which all agree. For the most part, and so far as the natural world is concerned, knowledge is always provisional, not restricted to an elite, and it grows as a result of “democratic” collaboration (see the quotation from Aristotle at the beginning of the chapter) and competition.23 This was the mainstream of Greek intellectual tradition. One had to distinguish between what could be known for certain and what could not be and develop tests or methods of argument that could be universally accepted. The Greeks had recognized that science is as much concerned with proving things false as with proving them true. Overall, this was a staggering achievement. In isolating and systematizing rational thought, the Greeks had founded science and mathematics in the form they are still followed today without implying that rational thought was the only path to truth. None of this would have been possible without an atmosphere of intellectual tolerance.
When the Greeks wrote about science, mathematics or any kind of systematic enquiry, including history or geography, they called their text a logos, or reasoned account. Logoi were typically written in prose, and their language reflected the nature of the task.24 The word logos itself, one of the most complex in Greek philosophy, came to take on other meanings, including “reasoned thought” itself. It was to re-emerge in a Christian context as “the Word” of God, although the relationship between God’s Word and reason itself was to prove problematic. The Greeks contrasted logos with muthos, an account in which reason plays no part. An obvious use of muthos is in telling a story about the gods (hence “myth”) or relating a narrative poem, and, in contrast to logoi, myths were normally related in verse. The important point to make is that myths were not devalued by the emergence of logoi. The Greeks realized that telling a story has its own uses far beyond entertainment and fulfills important emotional needs. Many cities focused their identity on foundation myths, which they used to foster the pride of their citizens.25 Myths were also used to underpin rituals at times of individual transition, from virginity to marriage, for instance. Perhaps the most sophisticated way in which the Greeks used myths was through tragic drama. Here a dilemma, based on the story lines of ancient myths, was presented in a play and acted through so that the consequences of the characters choosing one solution rather than another could be assessed by an audience, a truly democratic way of airing ethical issues. In his Poetics Aristotle argued that the purpose of tragic drama was to arouse pity and fear in the audience to give them some form of emotional catharsis, an experience which would make them more complete human beings.26
Aristotle’s support for the use of myth for human ends emphasizes that there is no necessary conflict between logos and muthos. Each has its value in its own context and neither threatens the other. One should not search for any form of absolute truth, in the sense of a belief whose certainty could be justified, in muthoi. Similarly, one should not use the word logos of truths that could not be defended by reasoned argument. Such a relaxed attitude to myth meant that the Greeks were tolerant and open about developing new stories about the gods and were able to speculate about their powers and attributes, even their very nature, without any sense of impropriety. Could the nature of the gods be grasped at all, asked Protagoras in the fifth century, in view “of the difficulty of the subject and the brevity of men’s lives”? Why should humans give the gods human form? asked the poet and natural philosopher Xenophanes; on this analogy horses would see their gods as horses. It is just as likely, Xenophanes went on, that there were gods, or even a single supreme divine figure, of a totally different nature from humanity. For Aristotle, reason suggested that there is a supreme “unmoved mover.” “Since motion must always exist and must not cease, there must necessarily be something eternal, either one thing or many, that first initiates motion, and this first mover must be unmoved.” Others suggested there were no gods at all. The world is totally material, argued the Atomists, with all matter being made up of tiny particles, atoms, literally “that which cannot be cut.” These more extreme forms of atheism did arouse concern. There remained a residual fear, certainly found among the population of Athens, for instance, that if the gods were rejected outright they might retaliate by withdrawing their patronage of the city. Sometimes this fear would erupt into intolerance, as in the case of Socrates, who was executed in Athens in 399 B.C. For the most part, however, Greek religion was undogmatic, its theology ever in flux. Myths and rituals were so interwoven into everyday life that no need was felt for an institutional hierarchy to defend them.27 Arguments over the divine were never restrained by doctrinal orthodoxy.
Although the achievement of the Greeks in establishing an atmosphere of tolerance in which considerable intellectual progress proved possible was remarkable, one should not idealize. We have already noted the difficulties in gathering empirical evidence and the way in which this limited what it was possible to know. Interpretation of empirical evidence also takes place within an ideological context. It was easy to rationalize from the observations of the human body that men were the active s
ex and women the passive, and the Hippocratic texts which concentrate on the diseases of women show how they were classified as “other” and how their organs, their “soft” flesh and their need to menstruate were explored within the context of male superiority. In her Hippocrates’ Woman: Reading the Female Body in Ancient Greece, Helen King shows how these attitudes persisted in the field of gynaecology (in the sense of a male profession telling women how they should regulate their bodies) well into modern times.28 Similarly, Aristotle links a hot climate to indolence and goes on to argue that those born in such regions are naturally slaves, available to the more active peoples, such as the Greeks, who have grown up in a relatively temperate environment. And it has to be remembered that even this level of “rational” thought was alien to most Greeks, who, it can be assumed, were oblivious to the sophisticated discussions of their educated peers. Irrationality flourished in the Greek world, much as it does, alongside scientific thinking, in ours.
The expanding use of rational thought can be seen as a symbol of the self-confidence of the Greeks, yet it was also fully accepted that human self-confidence had to be set within limits—no man should pretend he was a god. One reason, argues Herodotus, why the Persian king Xerxes was defeated when he invaded Greece in 480 was that his attempt to build a bridge across the Hellespont and to cut through a peninsula was an arrogant defiance of the natural order. He deserved his humiliation at the hands of the Greeks. Haughty behaviour (ate) or the deliberate humiliation of others ( hubris) were taboo. Such behaviour deserved the greatest humiliation of all, expulsion from the perpetrator’s native city, in addition to divine condemnation.
The Closing of the Western Mind: The Rise of Faith and the Fall of Reason Page 4