What was going on: Diogenes Laertius, writing centuries later, says Diogenes was captured by pirates on a voyage to Aegina, taken to Crete and put up for sale as a slave. His buyer, Xeniades, later put him in charge of his children and household in Corinth.
At the auction, asked what he was good at, he said: ruling people. Then he pointed at a man in a fine purple-bordered robe: sell me to him, he needs a master.
When the auctioneer asked in what he was proficient, he replied, In ruling men. Thereupon he pointed to a certain Corinthian with a fine purple border to his robe, the man named Xeniades above-mentioned, and said, Sell me to this man; he needs a master.