30. And he said he marvelled that before we buy a jar or dish we try whether it rings true, but if it is a man are content merely to look at him. To Xeniades who purchased him he said, “You must obey me, although I am a slave; for, if a physician or a steersman were in slavery, he would be obeyed.” Eubulus in his book entitled The Sale of Diogenes tells us that this was how he trained the sons of Xeniades. After their other studies he taught them to ride, to shoot with the bow, to sling stones and to hurl javelins. Later, when they reached the wrestling-school, he would not permit the master to give them full athletic training, but only so much as to heighten their colour and keep them in good condition.
31. The boys used to get by heart many passages from poets, historians, and the writings of Diogenes himself; and he would practise them in every short cut to a good memory. In the house too he taught them to wait upon themselves, and to be content with plain fare and water to drink. He used to make them crop their hair close and to wear it unadorned, and to go lightly clad, barefoot, silent, and not looking about them in the streets. He would also take them out hunting. They on their part had a great regard for Diogenes and made requests of their parents for him. The same Eubulus relates that he grew old in the house of Xeniades, and when he died was buried by his sons.