To judge from the number of his writings, his literary activity extended over a considerable period, but we have no means of assigning different works to different times in his life. He is variously reported to have lived between 90 and 109 years. On this evidence the date given for his birth by Apollodorus (in the 80th Olympiad, 460 –456 BCE) is generally preferred to that suggested by Thrasylus (the third year of the 77th Olympiad, 470 –469 BCE). He described himself in the Little World-System as a young man in the old age of Anaxagoras Diogenes La ërtius says that he was forty years younger than Anaxagoras. All this suggests that Leucippus was a slightly younger contemporary of Anaxagoras and that his main philosophical activity fell some time within the broad limits of 450 –420 BCE.ĭemocritus was born at Abdera. His book On Mind may have been directed partly against Anaxagoras, and according to Theophrastus, Diogenes of Apollonia derived some of his theories from Leucippus. Leucippus was probably born at Miletus reports associating him with Elea or Abdera should be taken as reflecting views concerning his philosophical affiliations rather than as reliable evidence for his birthplace. Epicurus is even reported to have said that there was no philosopher Leucippus, but the evidence of Aristotle decisively refutes this opinion (if, indeed, Epicurus did not merely intend to deny Leucippus's philosophical importance). We have very little biographical data for Leucippus. Moreover, the range of Democritus's researches surpassed that of any earlier philosopher, and he appears to have been an original and, for his day, advanced ethical thinker. 370 BCE) must go the credit for working out the detailed application of the theory and supporting it with a subtle epistemology. The originator of the atomic theory, Leucippus (fifth century BCE), must be considered a speculative thinker of the first order, but to Democritus (c. Leucippus and Democritus were the earliest Greek atomists.

Democritus atomic theory