Thales of Miletus was a Greek philosopher, mathematician, and astronomer. Considered by many including Aristotle to be the first philosopher in the Greek tradition. He is also considered the father of science by many and I sometimes refer to him as the grandfather of Western Philosophy.

Picture the busy port city of Miletus around 600 BCE: ships arriving from distant lands, merchants, sailors, and people were still explaining the natural world through mythology. Into that world came a thinker asking a different kind of question:

What if nature has natural explanations?

That shift is why Thales is still remembered more than 2,500 years later. At the time, the prevailing explanations of storms, earthquakes, life, and the structure of the world were the actions of gods. He changed that and that is scientific in nature. Hence, father of science. He looked for natural causes. He famously proposed that water was the underlying substance, or first principle, behind everything. That idea was wrong, but the method behind it was profound. He looked at the world around him; he noticed patterns; he tried to explain one part of nature with another part of nature. In modern terms, he was asking whether what we see might emerge from something more fundamental.

His works were lost over the centuries, but we know Thales through later writers. About two centuries later, Aristotle looked back on him as the beginning of the Greek tradition: the search for the underlying causes and principles of nature. Aristotle specifically recording his claim that water was the first principle. Later ancient writers continued to place him among Greece’s earliest sages. His lasting importance is not that he gave us the right answers. It is that he helped point Western thought toward a new way of finding them.