• Born year: 0005
  • Born in: Miletus
  • Death year: 0005

Leucippus (/luːˈsɪpəs/; Greek: Λεύκιππος, Leukippos; fl. 5th century BCE) was one of the earliest Greeks to develop the theory of atomism — the idea that everything is composed entirely of various imperishable, indivisible elements called atoms — which was elaborated in greater detail by his pupil and successor, Democritus. According to this atomism, if you take a piece of wood and then cut it into two equal parts, then do it continuously, eventually you will find a part that you cannot cut.