Democritus was a Greek philosopher known for his idea that the universe consisted of small, indivisible units of matter - which he called atoms - and the void in which they exist. This contrasted with the commonly held belief that matter could always be divided into ever smaller pieces, each of which would contain the same basic properties as the material from which it derived.

Ultimately, Democritus became known as the originator of this theory of atomism, although he probably learnt some of it from his teacher, Leucippus.

Despite the alliterative qualities of their names, Democritus is not generally known for his contributions to the political theory of democracy.