It's All Greek To Me
At the beginning of the sixth century there lived in Miletus, in Ionia, a man called Thales. According to Plato, in his dialogue Theaetetus, Thales died by falling into a well while he was gazing on the heavens, poor fellow. If early Greek science can, occasionally, come under fire for being insufficiently empirical and too focused on the assertion and counter-assertion of cosmological theories, then at least tradition has it that the man credited with the founding of Greek science—and philosophy—was interested, to a fault, in observing natural phenomena. You might say that Thales, not looking where he was going, also gives us the foundation myth of the mad professor, of the thinker so wrapped up in important abstractions that everyday concerns fall by the wayside.
In ancient Greece there was no word for what we would term science, as such, and the earliest thinkers, who now tend to be referred to under the umbrella term of 'pre-Socratic philosophers,' would likely have described what they were doing as conducting 'enquiries'—which is what Herodotus the historian was doing, albeit from a slightly different perspective. What Thales and co had in common with Herodotus
is that they tried to explore natural (or, in Herodotus' case, historical) phenomena without explaining them in terms of the gods or of the supernaturd. To begin to try to explain the world as a sequence of rationally explicable events—to say that storms at sea are not sent by Poseidon; nor is lightning Zeus' thunderbolt—was an intellectual shift of extraordinary power, as significant, if not more so, than the intellectual shifts that ushered in the Reformation, or the Enlightenment. It was a move that cleared the pathways for the riches of philosophical, literary and political developments of the fifth century and put man, rather than the gods, at the centre of the universe.
Still, fans of ancient Egypt and Babylon might point out, with justice, that way before the Greeks got going, enormous advances had been made in mathematics and astronomy (a debt that Plato himself acknowledged). The Babylonians, for instance, actually had a reasonably accurate calendar, which is more than the Greeks could manage. In a typically chaotic manner, each of the Greek poleis had their own version of the calendar, with different names for the months, and based on a lunar system—which, of course, does not dovetail with the solar system. If you calculate your calendar on the basis of lunar months, there will be 10 or so days left over each year. So every few years, if things felt out of synch, if a midsummer month didn't feel sufficiently midsummery, a city state would simply have the month again, to even things out.
The work of the early scientists is often preserved in tiny fragments, or expressed in rather obscure and gnomic terms, or known only as quoted or summarised by later writers; piecing their theories together is a delicate, and often contentious task. Thales put forward the theory that the world was held up by water; and that earthquakes, far from being the work of Poseidon, were the result of wave tremors from below the earth. Anaximander, another Milesian, perhaps Thales' pupil, wrote a prose treatise, called On the Nature of Things, he is thus responsible for one of the first-preserved prose sentences in Greek. (The very first writer of Greek prose is reputed to be Pherecydes of Syros in the Cyclades, who wrote about the gods and the creation of the cosmos in the mid-sixth century.) For Anaximander, the governing principle of the world, what 'held it up,' was the Boundless, or the Infinite (which is an attempt to answer the question left hanging by Thales, that is, what holds the water up?). Anaximander was responsible for the first attempt in Greek astronomy to posit a mechanical model for the heavenly bodies: the earth is a flat-topped cylinder, he held, while the sun, moon and stars are formed by hidden wheels of fire. (In other words, he proposed that what we see as a star 'is like a puncture in a vast celestial bicycle wheel,' as one eminent writer on Greek science puts it.) Symmetry is key to Anaximander's conception: opposites are separated out to generate the hot and the cold, the dry and the wet. His pupil, Anaximenes, who was working during the third quarter of the sixth century proposed on the other hand that air was the primary material: as breath governs humans, so air governs the world. To explain change and world formation, he offered the idea of condensation and rarefaction of the air: air becomes fire by rarefaction, condenses to become water and again to become stones.