Phaedo is a philosophical dialogue by the Ancient Greek philosopher Plato about Socrates' arguments for the soul's immortality. Shortly before his execution, Socrates makes four arguments for why the soul must be immortal: a cyclical theory that things are born of their opposites and that death and life are therefore dialectically interrelated, a recollection theory that humans possess innate knowledge at birth and therefore must have existed before and after corporeal life, and two other arguments that focus on the soul's immortality because of its participation in metaphysical forms.
Euthyphro, Apology, Crito and Phaedo are four philosophical dialogues sorrounding the trial and death of Socrates, written by the Ancient Greek philosopher Plato. In the Euthyphro, Socrates is awaiting trial and attempts to find a universal definition for piety. The Apology is an account of Socrates' speech during his trial, defending himself against charges of blaspheme and corrupting Athenian youths. Crito is a dialogue about justice and social obligation in which Socrates accepts his death sentence. In Phaedo, Socrates attempts to prove the immortality of the soul.