(Greek Διογένης) A controversial Greek philosopher who extolled poverty as virtuous, begged for a living, and slept in a tub in the marketplace. He was notorious for his provocative and confrontational behavior, and was one of the only people to survive publicly insulting Alexander, who deeply respected Diogenes. One story relates that Diogenes walked the city carrying a lamp in the daytime, looking for an true man but not finding any.