He was a homeless man who shit in people’s lawns lol. I know a couple stories, he’s a huge troll. Plato was teaching a class, where they defined human as “hairless and bi-pedal”. So Diogenes plucked a chicken and brought it to class and said “Behold!! A man!”. Diogenes was washing some vegetables in a river (naked of course) and Plato approached him and said “Diogenes, if only you could pay taxes to the king, you wouldn’t have to wash your food in a river.” And Diogenes replied “Plato, if only you could wash food in a river, you wouldn’t have to pay taxes to the king.” Diogenes was sun bathing on a beach (naked) when Alexander the Great approached him. Being a fan he told Diogenes (who was still laying naked in the sand) that he wanted to give Diogenes a gift. Anything within Alexander’s power to give, just ask. So Diogenes asked “Could you take a few steps to the side? You’re blocking the sun.” I have no sources just things I’ve heard lol