The oracle said no one was wiser. Socrates tried to prove it wrong.

Socrates’ friend Chaerephon once travelled to the Oracle of Delphi and asked a bold question: was anyone wiser than Socrates? The priestess answered that no one was.

Socrates, in Plato’s account, was baffled. He was sure he knew nothing of real importance. So he set out to find someone wiser and bring him back as proof that the god was mistaken.

He questioned politicians, poets and craftsmen. Each was confident about many great things, and under questioning each turned out to know far less than they believed. The craftsmen really did know their trade, but assumed that made them experts in everything else.

Slowly Socrates understood the oracle. He was wiser in only one small way: he did not think he knew what he did not know. That became his life’s work, and the reason Athens eventually put him on trial. Asking people questions, it turns out, can be more dangerous than giving them answers.