The Honest Mirror

Diogenes served as Athens' living conscience. When politicians made grand speeches about justice, he asked why they had not returned stolen property. When philosophers debated abstract virtue, he noted they were doing it over expensive wine they did not share.

His method was confrontation through behavior, not argument. You cannot debate someone living their principles in front of you. He did not say wealth is meaningless — he proved it by being the most memorable person in Athens while owning nothing.