Critias (; ,
Kritias; c. 460 – 403 BCE) was an
ancient Athenian political figure and author. Born in Athens, Critias was the son of Callaeschrus and a first cousin of
Plato's mother
Perictione, and became a leading and violent member of the
Thirty Tyrants. He was an associate of
Socrates, a fact that did not endear Socrates to the Athenian public.