The Sophists begin their grammatical analysis of…

The Sophists begin their grammatical analysis of Greek around 400 or a little earlier.

Contrary philosopher-educator Socrates, about seventy in 399, is accused by the Athenian government of impiety and of corrupting the youth of the city by questioning tradition.

The example of undisciplined and restless ambition displayed by the charming, brilliant, but unscrupulous Alcibiades, who could not practice his master's virtues, strengthens the charge.

On trial for his life before an Athenian jury, Socrates (according to Plato's later Apology, whose title is from the Greek word for defense) declares himself thoroughly innocent of the charges against him, countering that his accusers are motivated by resentment caused by his deflation of their pretended wisdom.

His own wisdom, he says, consists of knowing that he is not wise, and his relentless questioning of people's assumptions is prompted by an inner voice, a “daimon,” which must be obeyed, regardless of the consequences.

Instead of being punished by the state, it should reward him for acting as its "gadfly."

The unexamined life, says Socrates, is not worth living. (Xenophon offers a different account of the defense in his Apology of Socrates.)

The government convicts Socrates and orders him to take his own life by poison.

Following the trial, his friends arrange for him to escape, but rather than do wrong to the city by flouting its laws he remains in prison and suffers the death penalty. (Plato's Phaedro records the philosopher's death scene.)

Socrates' famously shrewish wife, Xanthippe, dies about the same time.