Philosophy begins: Thales’ revolution

In raising the question of why philosophy begins with Thales, we first looked at Homer, the great shaper of the Greek mind before the philosophical and scientific revolution: Before philosophy: Homer’s world. In that post, I abstracted five statements from The Iliad:

homer_british_museum-50x63H1. Supernatural causation is part of the explanation for natural events.
H2. Supernatural causation is more powerful than natural causation.
H3. The supernatural is personal.
H4. Consequently, supernatural causation is sometimes whimsical and so inconsistent and so makes long range prediction unreliable.
H5. Consequently, ethics is a matter mostly of power — revere gods and kings not because they’re just but because they’re powerful.

Now let’s return to Thales and the birth of a new worldview:

thales-100x128“The first principle and basic nature of all things is water.”

Thales’ first principle is water. If it is water, then it is not the gods. The gods have become at most secondary, so we have at least an implicit challenge to H2.

Also, the basic nature of all things is water. Water is a natural phenomenon, not a supernatural one, so we have at least an implicit denial of H1.

Why water? No doubt Thales has observed the weather cycle, the flowing of rain into streams and eventually to the sea, the critical importance of water to all living things, that water can be transformed from liquid to solid and back and from liquid to gas and back — and that it does so with a regularity. It’s not that nobody had noticed regularities in nature before Thales. But if water is the first principle of all of things, then all of reality is regular. So we have at least an implicit challenge to H4.

We are well on our way to thinking of nature as a self-contained, self-governing, regular physical system of cause and effect.

It’s also clear that Thales’ statement is based on observations of transformations from liquid to gas to solids, and so on. So he is not basing his views on traditional stories handed down through the ages. And he is offering an explanatory hypothesis for those observations. Observation integrated with explanation is a hallmark of a naturalist, philosophical approach.

Subsequent Presocratics argued with Thales. (By contrast, who would ever argue with Homer?) Anaximenes held that fire was a better first-principle candidate than water, as did Heraclitus. Anaximander (my favorite Presocratic) held that having only one basic state of being, whether water or fire, was too reductionist, and so proposed that water, air, earth, and fire were in a cyclical transformation in and out of a “boundless” state. And others entered the fray.

The Presocratics are now using reason in a different way. It’s not clear that they are self-conscious about the new method of thinking. But they are no longer thinking in Homeric principles and the new thinkers very quickly become incredulous and scornful when the Homeric and other stories are taken as more than fanciful literature. Hecataeus of Miletus (550-489), who died 19 years before the birth of Socrates, is representative:

“What I write here is the account of what I considered to be true. For the stories of the Greeks are numerous and, in my opinion, ridiculous.”

A new way of thinking has begun. Philosophy and the sciences have been launched and quickly flourish.

As for H5 and the development of a philosophical approach to ethics, that story is worth another, later post, and involves the innovations of Hesiod and other giants. Great stuff.

Related: Medical politics in ancient Greece.

7 thoughts on “Philosophy begins: Thales’ revolution”

  1. In “Night Sky at Rhodes” Toulmin makes a very clever conjecture about Thales’ view that water is the “original” of all things. (I’m assuming Toulmin came up with this conjecture, but it may have been someone else.) The rivers of Asia Minor that flow into the Aegean are notoriously silty, and many of the great cities of Thales’ time, such as Miletus, have been abandoned for centuries because their harbors long ago silted up. Miletus was a great commercial port; today its ruins lie several miles inland, surrounded by farm fields. The process of siltation is easily observable, and would have been in Thales’ time as well. Toulmin suggests that Thales was simply making a direct empirical observation: the world was clearly “drying out” (the land area was increasing and the water area decreasing), and if you simply project backward in time, it’s obvious that long ago the world must have been all water.

  2. I like the hypothesis. Coincidentally, that Toulmin book arrived in the mail this week and last night I got as far as looking through the pictures and reading the anecdote about watching the solar eclipse from Italy.

  3. The change in Greek thinking shows in another way as well. In Homer (the Trojan War), the gods and goddesses seem to run everything. In Herodotus (the Persian War) there are fewer references to the supernatural. By the time we come to Thucydides (the Peloponnesian War) the account it completely secular. Thucydides was a contemporary of Socrates.

    Bob Marks

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