The Decree of Diopeithes was instituted by the opponents of Pericles in an attempt to discredit Anaxagoras, [1] and, through so doing, to discredit Pericles himself through his association with Anaxagoras. [2] The date is not exact, as sources give different years. Some sources list the arrest and trial of Anaxagoras as early as 437/6 BCE, [3] others at 434 BCE, [4] and still others 432. [5] The charges stemmed from his observations of the heavens and asserting that there were no lunar and solar deities. [6] [7]
According to the Oxford Classical Dictionary, the only reference to this decree comes from Plutarch's Pericles:
And Diopithes proposed a decree, that public accusations should be laid against persons who neglected religion, or taught new doctrines about things above, directing suspicion, by means of Anaxagoras, against Pericles himself.
— Plutarch, Pericles , para. 32
A reference to the trial of Anaxagoras was mentioned by Plato in Apology:
That is an extraordinary statement, Meletus. Why do you say that? Do you mean that I do not believe in the godhead of the sun or moon, which is the common creed of all men?
I assure you, judges, that he does not believe in them; for he says that the sun is stone, and the moon earth.
Friend Meletus, you think that you are accusing Anaxagoras; and you have but a bad opinion of the judges, if you fancy them ignorant to such a degree as not to know that those doctrines are found in the books of Anaxagoras the Clazomenian, who is full of them.
— Plato, Apology
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