Anaximander c. 610–546 BCE

In the bustling, sun-baked streets of Miletus, where merchants argued over grain prices and sailors cursed the shifting winds, there lived a man who tried to think past the edge of the visible world. To most people in that Ionian city, the horizon at sea was a simple line: beyond it lay other ports, other gods, other dangers. For Anaximander of Miletus, that hazy band between water and sky was something more. It was an invitation to imagine a structure larger than anything the senses could directly show. Where others saw the earth as resting on something—water, pillars, the back of some creature—Anaximander dared to ask, what if it rests on nothing at all?He lived in the sixth century BCE, a younger contemporary and likely associate of Thales, who is often called the first philosopher. If Thales was the one who said, “all is water,” Anaximander was the one who answered, “no, not water, but something more abstract, something that cannot itself be any familiar element.” In a culture just beginning to peel myth away from explanation, that move is astonishing. It means that less than a century after Greeks first began to search for a single underlying principle of the world, someone was already questioning whether any concrete, visible substance could serve in that role. Anaximander steps beyond water, air, earth, and fire, and names the first principle the apeiron: the “indefinite,” the “boundless,” that which has no fixed quality, shape, or limit.Selenius Media