Editing Ancient Greek philosophy (section)

=== Milesian school ===
{{Main|Milesian school}}
[[Thales of Miletus]], regarded by [[Aristotle]] as the first philosopher,<ref>[[Aristotle]], [[Metaphysics (Aristotle)|''Metaphysics Alpha'']], 983b18.</ref> held that all things arise from a single material substance, water.<ref>Aristotle, ''Metaphysics Alpha'', 983 b6 8–11.</ref> It is not because he gave a [[cosmogony]] that [[John Burnet (classicist)|John Burnet]] calls him the "first man of science", but because he gave a naturalistic explanation of the [[cosmos]] and supported it with reasons.<ref>Burnet, ''Greek Philosophy'', 3–4, 18.</ref> According to tradition, Thales was able to predict an [[solar eclipse|eclipse]] and taught the Egyptians how to measure the height of the [[pyramids]].<ref>Burnet, ''Greek Philosophy'', 18–20; [[Herodotus]], [[Histories (Herodotus)|''Histories'']], I.74.</ref>

Thales inspired the [[Milesian school]] of philosophy and was followed by [[Anaximander]], who argued that the substratum or [[arche#Arche in ancient Greek Philosophy|''arche'']] could not be water or any of the [[classical element]]s but was instead something "unlimited" or "indefinite" (in Greek, the ''[[Apeiron (cosmology)|apeiron]]''). He began from the observation that the world seems to consist of opposites (e.g., hot and cold), yet a thing can become its opposite (e.g., a hot thing cold). Therefore, they cannot truly be opposites but rather must both be manifestations of some underlying unity that is neither. This underlying unity (substratum, ''arche'') could not be any of the classical elements, since they were one extreme or another. For example, water is wet, the opposite of dry, while fire is dry, the opposite of wet.<ref>Burnet, ''Greek Philosophy'', 22–24.</ref> This initial state is ageless and imperishable, and everything returns to it according to necessity.<ref>{{Cite book|url=https://books.google.com/books?id=ogUR3V9wbbIC&pg=PA83|title=A History of Greek Philosophy: Volume 1, The Earlier Presocratics and the Pythagoreans|first1=W. K. C.|last1=Guthrie|first2=William Keith Chambers|last2=Guthrie|date=May 14, 1978|publisher=Cambridge University Press|isbn=9780521294201|via=Google Books}}</ref> [[Anaximenes of Miletus|Anaximenes]] in turn held that the ''arche'' was air, although John Burnet argues that by this, he meant that it was a transparent mist, the [[aether (classical element)|''aether'']].<ref>Burnet, ''Greek Philosophy'', 21.</ref> Despite their varied answers, the Milesian school was searching for a natural substance that would remain unchanged despite appearing in different forms, and thus represents one of the first scientific attempts to answer the question that would lead to the development of modern atomic theory; "the Milesians," says Burnet, "asked for the [[physis|''φύσις'']]<!--Greek italics in the original--> of all things."<ref>Burnet, ''Greek Philosophy'', 27.</ref>