(c. 460—370 bc) Greek philosopher
(b. c.460 bc),
a celebrated Greek philosopher, born at Abdera. He advanced (with Leucippus) the theory that the world was formed by the concourse of atoms, the theory subsequently expounded by Lucretius and confirmed and developed by recent scientific discovery. Juvenal speaks of him as ever laughing at the follies of mankind, and he is sometimes known as the ‘laughing philosopher’.