"I cannot approve of Heraclitus, who, being self-taught and arrogant, said, "I have explored myself." Nor can I praise him for hiding his poem in the temple of Artemis, in order that it might be published afterwards as a mystery; and those who take an interest in such things say that Euripides the tragic poet came there and read it, and, gradually learning it by heart, carefully handed down to posterity this darkness of Heraclitus."