Diagoras of Melos was a lyric poet and the first Greek philosopher known specifically for his atheism. Heavily influenced by Democritus, the early Greek natural philosopher and advocate of atomism, who in fact was his tutor, Diagoras ran afoul of religious conservatives in Athens and had to flee the city with a price on his head (he was wanted dead or alive).
About Diagoras, Jennifer Michael Hecht, author of Doubt: A History, wrote
The poet Diagoras of Melos was perhaps the most famous atheist of the fifth century. Although he did not write about atheism, anecdotes about his unbelief suggest he was self-confident, almost teasing, and very public. He revealed the secret rituals of the Eleusinian mystery religion to everyone and “thus made them ordinary,” that is, he purposefully demystified a cherished secret rite, apparently to provoke his contemporaries into thought. In another famous story, a friend pointed out an expensive display of votive gifts and said, “You think the gods have no care for man? Why, you can see from all these votive pictures here how many people have escaped the fury of storms at sea by praying to the gods who have brought them safe to harbor.” To which Diagoras replied, “Yes, indeed, but where are the pictures of all those who suffered shipwreck and perished in the waves?” A good question. Diagoras was indicted for profaning the mysteries, but escaped. A search was out for him throughout the Athenian empire, which indicated that the charges were serious, but he was not found.
—“Whatever Happened to Zeus and Hera?, 600 BCE-1 CE” in Doubt: A History, Hecht, Jennifer Michael, Harper, San Francisco (2003), pp. 9–10
The Christian writer Athenagoras of Athens (2nd century AD) writes about Diagoras:
Not only did Diagoras chop up a wooden statue of Hercules, but exhibited his wit by declaring that Hercules thirteenth labor would be cooking turnips.
Of Diagoras, JM Robertson writes,
It was about that time [415 BC] that the poet Diagoras of Melos was proscribed for atheism, he having declared that the non-punishment of a certain act of iniquity proved that there were no Gods. It has been surmised, with some reason, that the iniquity in question was the slaughter of the Melians by the Athenians in 416 B.C., and the Athenian resentment in that case was personal and political rather than religious. For some time after 415 the Athenian courts made strenuous efforts to punish every discoverable case of impiety; and parodies of the Eleusinian mysteries were alleged against Alkibiades and others. Diagoras, who was further charged with divulging the Eleusinian and other mysteries, and with making firewood of an image of Herakles, telling the god thus to perform his thirteenth labour by cooking turnips, became thenceforth one of the proverbial atheists of the ancient world, and a reward of a silver talent was offered for killing him, and of two talents for his capture alive; despite which he seems to have escaped.
—A History of Freethought, Ancient and Modern, to the Period of the French Revolution, J.M. Robertson, Fourth Edition, Revised and Expanded, In Two Volumes, Vol. I, Watts, 1936. p173 – 174
The following account of Diagoras is translated from the Suda
[Diagoras], son of Telekleides or Teleklytos; a Melian, a philosopher and a lyric poet; whom Democritus from Abdera, seeing that he was naturally talented, bought — since he was a slave — for ten thousand drachmas and made a pupil. And he also applied himself to the lyric art, being in time after Pindar and Bacchylides, but older than Melanippides: he flourished in the 78th Olympiad. And he was called Atheos since he held such an opinion, after the time when someone of the same art, being accused by him of stealing a paean which he himself had made, swore he did not steal this, and performing it a short while later, met with success. Thereupon Diagoras, being upset, wrote the so-called Apopyrgizontes Logoi, which includes his withdrawal and falling away from his belief concerning the divine. But Diagoras, settling in Corinth, lived out his life there.
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