Now there was in Corinth at that time a man named Demetrius, who studied philosophy and had embraced in his system all the masculine vigor of the Cynics. Of him Favorinus in several of his works subsequently made the most generous mention, and his attitude towards Apollonius was exactly that which they say Antisthenes took up towards the system of Socrates: for he followed him and was anxious to be his disciple, and was devoted to his doctrines, and converted to the side of Apollonius the more esteemed of his own pupils.
Source: The Loeb Classical Library. Philostratus. The Life of Apollonius of Tyana, the Epistles of Apollonius, and the Treatise of Eusebius with an English translation by F.C. Conybeare M.A. In two volumes. London and New York: MCMXXI.