| Presocratics Index | Intro | Thales | Anaximandros | Anaximenes | Herakleitos | Parmenides | Zenon | Melissos |
| Atomists: Leukippos and Demokritos | Anaxagoras | Empedokles | Significance of the Presocratics |

If we define physics as the study of matter and changes in matter, then we may search for its origins in a tradition of critical debate established by the presocratic natural philosophers who lived in early Greek colonies scattered, for the most part, around the Aegean Sea, before the time of Socrates. With the exception of the Pythagoreans, presocratic speculations in natural philosophy were distinct from the mathematical approach to interpreting nature we explored last week in the astronomy of ancient Mesopotamia and to which we will return again next week with Pythagoras and Plato. To appreciate the presocratics, we should keep in mind something of (i) the geography of the Aegean, (ii) their significance for the history of science, and (iii) their social and religious cultural contexts. This page touches briefly on each of these three topics in turn.

I. Geography

The twelve Greek city-states of Ionia, located in western Asia Minor (modern Turkey), were the original home of most presocratic philosophers we will consider here. The shores of the Aegean Sea include Greece on the west, a complex of islands to the south, Asia Minor on the east, and Macedonia on the north. The following map is provided by the Interactive Ancient Mediterranean. Like many maps, it refers to locations using their Latin names.

Note on Greek and Latin spelling of names: When Greek names were transliterated into Latin, there were many simple changes. For example, places ending in "-os" were changed to "-us"; "k" was changed to "c," and "ai" was changed to "ae." We will refer to the names in Greek so long as we are studying the Greeks themselves, but you should have little trouble identifying any location or person by its/their Latin name.

Locate the following towns on the map:

Click the map for a larger, print-quality pdf (copyright Interactive Ancient Mediterranean).

II. Significance for the history of science; or, Why study the Presocratics?

What is nature, and how is nature known?

Nature, physis: One of the most important concepts to consider as we explore these questions is the meaning of the word "nature," or in Greek, "physis." What did "physis" mean before the presocratics?

Homer (ca. 800 BC) described someone pulling up a weed to examine its physis, by which he meant its form. Xenophanes’ On the Art of Horsemanship advised the reader only to rub a horse down in the direction which the hair naturally (physin) grows. These two usages of "nature" or "natural" represent the typical pre-theoretical meaning of nature (physis) as "that which usually or regularly happens" during, or results from, a process of change. This is what the term "nature" meant before the presocratic natural philosophers (and later Aristotle) got hold of it and fundamentally changed its meaning.

We shall see next week that Aristotle made physis a technical term to refer to that which changes according to an internal principle. The growth of a tree is "natural" change because it is governed by the internal principle of the tree found initially in the seed. To transform a living tree into a wooden bed would not be natural change, but art (techne), where the principle of change is external (the craftsman) rather than internal (the seed). Those philosophers who study physis, that is, changes occurring according to an internal principle, Aristotle called physiologoi, or physicists.

Most of our knowledge of the origins of the abstract Greek debate about nature (physis), which became known as physics, depends upon Aristotle’s account (as related in two of his books, the Physics, Bk II, and Metaphysics, section A). Thus our historiography is liable to many of the dangers of anachronism commonly associated with retrospective explanations for a present state of affairs. Yet it was Aristotle’s regular practice when raising any question first to survey the opinions and arguments of others who had considered the given topic. This was his means of ensuring the comprehensiveness and thoroughness of his account, and it is the chief reason the fragments of the presocratics were preserved and have been studied from ancient Greece all the way up to today. It will be our task to appreciate the continuities he discerned between their endeavors and his own (and even up to modern physics), while also keeping in mind what Aristotle did not tell us about the religious and social contexts of the presocratics' own concerns. For example, if "nature" meant "that which regularly occurs," then how was nature understood as related to contemporaneous religion? This question was not at the heart of Aristotle's concern. We will return to this question below.

As we shall see, the presocratic natural philosophers articulated many of the fundamental questions of natural philosophy, or physics. They established the importance of debate over foundational scientific ideas. They initiated a long-standing debate on the meaning of “nature.” They demonstrated the power of knowing nature theoretically as well as empirically. Their focus on the problem of change in nature was particularly influential in shaping the views of Plato and Aristotle, and therefore of scientific traditions through the early modern period. And they created a framework of critical debate encompassing a wide range of various alternative options within which scientific theories could be developed. These theoretical alternatives included:

We shall explore each of these theoretical options in the following pages. Keep in mind that theoretical knowledge in science is often different from empirical knowledge. The presocratics were skeptical of observation, for the senses often deceive us. Therefore they relied upon intellectual argument, or theoretical activity, as the best way of knowing nature.

III. Contemporary social and religious cultural contexts

The scientific accomplishments we have explored for ancient Mesopotamian and Egyptian cultures were achieved in the context of powerful centralized states capable of marshalling resources and manpower for large collaborative projects, or builidng institutions to be staffed by elite priests. Not so with the presocratics. Perhaps the most obvious initial contrasts between the presocratics and the cultures we have looked at so far are the poleis (city states) and literacy:

This monistic religious reform was an interesting movement away from polytheism that paralleled the presocratics' movement toward a monistic natural philosophy.

There were also external influences for monistic religious reform:

Indeed, the 600's B.C., the century immediately preceding the first of the presocratics, is often referred to as "the orientalizing period" because of the numerous cultural interactions between Greece, Asia Minor and Mesopotamia -- see, for example, Walter Burkert, Babylon, Memphis, Persepolis: Eastern Contexts of Greek Culture (Harvard, 2004); and Heinrich von Staden, "Affinities and Elisions, Helen and Hellenocentrism," Isis, 1992, 83: 581-582.

As you read the following pages, ask yourself this question: Are presocratic theories best understood as a repudiation of all religion in favor of science, or as a reform movement advocating a more monistic or dualistic religious ethos against the polytheism and anthropomorphism of the Olympian gods? You make the call.

Before going on, review some important definitions: