Influence . Though exact details of Milesian speculation are often difficult to capture, its significance is clear and hard to overstate. It is especially important for the degree to which it embodies influential trends that later became more explicit in the history of Greek scientific thought. The Milesians were the first to distinguish consistently between what is natural and what is supernatural, and also to exploit that distinction. These two categories might well be familiar to us now, but for thinkers in the sixth century b.c.e., the difference between them was revolutionary. The theories of Thales, Anaximander, and Anaximenes are as remarkable for what they omit as for what they actually say. Against a background of mythical and religious accounts of the origin and nature of the world, they instead declared that valid explanations of events must be found in regular, rational patterns of natural causes and effects, instead of in the arbitrary will of supernatural forces. Of course, Thales’ claim that earthquakes happen because the earth rocks back and forth on choppy water is in reality no more true than the pious belief that they are caused by an angry god named Poseidon, waving his trident at the bottom of the sea. By excluding gods and other supernatural causes from their explanations, however, Thales and the other Milesians created a new way of thinking and talking about the world. Rational claims could now challenge traditional beliefs.
Consistency. Another scientific feature of their work is the fact that the Milesians seem to have focused their attention on studying types rather than particulars. That is to say, they viewed earthquakes, for example, as a class of events instead of as a unique thing that happens now and then, here or there, as Poseidon wills it. For the Milesians, rational accounts should be as comprehensive as possible and, ideally, universally applicable, true for every instance they seek to explain.
Uncovering the Truth. Milesian speculation aimed, as Aristotle later put it, to “save the phenomena” (sôizein ta phainomena) by uncovering the universal truths they embody, the rational principles that underlie a multiplicity of singular events. The term saving here chiefly means “rescuing” phenomena by building explanatory frameworks in which the events can be understood; without such frameworks, they are simply “lost” and unintelligible. True to this aim, early Greek speculation exhibited a strong tendency to generalize—often (and even absurdly) far beyond the available evidence—in order to include more and more things under a single explanation. The simpler and more inclusive the explanatory framework, after all, the greater its explanatory power and the stronger its claim to being genuine science.
According to the Pythagoreans, ten was the essence of all numbers. Moreover, the power of 10 resided in the tetrad, or number 4. If you began at 1 and kept adding each successive number up to four, you arrived at the number 10 (1 + 2 + 3 + 4 = 10), In terms of single units, it was the number 10, but in terms of potentiality, it was the number 4, As a result, the Pythagoreans used to invoke the tetrad as their most sacred oath: “By him who gave the tetrad to our generation, which holds the source and root of eternal reality.”
Source: Walter Burkert, Lore and Science in Ancient Pythagoreanism, translated by E. L. Minar Jr. (Cambridge, Mass.: Harvard University Press, 1972).
Nature. The fact is that the Milesians might well even be said to have invented nature itself, in the sense that their efforts helped to shape the concept of a naturalistic, rational world. Their work created a new category of events—namely, events whose explanation is not to be found by searching the heavens for signs of divine, supernatural activity. Instead, this new category of nature includes all those
events whose explanations are (or potentially could be) rational. By doing so, the Milesians implicitly defined the object of all later Western science as a collection of regular causes and effects governed by law-like principles. This approach is clearest with Anaximenes, whose identification of condensation and rarefaction as the forces behind all change had the effect of defining the world as an orderly system of simple, physical processes.
Power of Reason. Moreover, if nature is reasonable, it can be understood best by using human powers of reason. This argument may seem obvious, and even a little circular, but it nonetheless marks an important step in the development of scientific thinking. It is a question of which tool is appropriate for which job. If everything that happens in the world results from die behavior of supernatural beings, then events can be understood only in terms of personal decisions made by gods. Since personal decisions are generally influenced by emotions and feelings more than logic, the powers of reason are inadequate to explain and predict them. Nature can be better understood and expressed by rational minds using regular, orderly, law-like principles of reasoning. Hard critical thinking—not blind acceptance of authority, pious emotion, or prayer—opens the way to true knowledge about the world.
The logos holds always but humans always prove unable to understand it, both before hearing it and when they have first heard it. For though .affl things, happen in accordance with this logos, hutaans are like people with no experience when they experience what I say and do …
Although the logos is common, most people Eve as if they had their own private understanding.
Misunderstanding what they have heard, they are like the deaf. This saying describes them: though present, they are absent.
Pigs prefer mud to pure water.
Listening not to me but to the logos, it is wise to agree that all things are one.
They do not understand how, though at variance with itself, it agrees with itself. It is a baekwardsrturriing attunement, like that of the bow and the lyre.
An unapparent connection (harmonia) is stronger than an apparent one.
On the circumference of a circle, beginning arid end are the same.
The name of the bow (bios) is life (bios), but its work is death.
Changing, it rests.
God is day night, winter summer, war peace, satiety hunger; he undergoes alteration just as fire, when roiled with spices, gets its name from the scent each gives to it. Different and different waters flow on those who step into the same rivers twice.
Source: Richafd D. McKirahan* ed., Philosophy before Socrates: An introduction with Texts and Commentary (Indianapolis: Hackett, 1994).
Debates. Just as important, this early speculation developed in a context of open debate. The freedom with which the Milesians rejected supernatural explanations already implies a kind of deliberate confrontation, a contest between modern ideas and traditional lore. At the same time, the new thinkers also seem to have been engaged in vigorous, public competition with each other; this approach is indeed a feature of all Greek science, and perhaps of Greek culture as a whole. Anaximander’s proposal of the Limitless looks like an abstract challenge to the simple, material stuff claimed by Thales; and in the notion of contracting and expanding air there seems to be an attempt by Anaximenes to solve what was problematic or lacking in both earlier theories. Whether passion for debate reflected Greek political and social conditions—the Milesians lived during a time of political instability, amidst many competing forms of government—or whether it helped create them is a good question. Whatever the answer, the critical climate encouraged these early thinkers to challenge ancient religious beliefs, to analyze claims and counterclaims carefully, to search for compelling evidence to support new theories, and eventually to create a language appropriate for rational, scientific discourse.
David C. Lindberg, The Beginnings of Western Science (Chicago: University of Chicago Press, 1992).
Geoffrey Ernest Richard Lloyd, Early Greek Science: Thales to Aristotle (New York: Norton, 1970).