While some scholars question his "professional" status as a sophist, he is typically grouped with them due to his rationalism and radical challenges to traditional values.
Critias was a complex figure in the "Sophistic Enlightenment" of late 5th-century Athens. Unlike itinerant sophists like Protagoras or Gorgias, he was a native Athenian and a relative of Plato.
He was the most violent leader of the Thirty Tyrants , the pro-Spartan oligarchy that ruled Athens after its defeat in the Peloponnesian War.