480?-420? B.C.

Greek philosopher best known as the founder of atomism, the notion that all matter is composed of indestructible atoms; this concept was further elaborated in the writings of his pupil Democritus of Abderra. It is possible that Leucippus studied under the philosopher Zeno of Elea, whose paradoxes about motion stimulated much Greek physical speculation. The one surviving fragment of his written work expresses a deterministic view of the world with no room for chance events.