A Dictionary of Greek and Roman biography and mythology

3. Surnamed the BABYLONIAN, a Stoic philosopher. He was a native of Seleuceia in Babylonia, from which he derived his surname in order to distinguish him from other philosophers of the name of Diogenes. He was educated at Athens under the auspices of Chrysippus, and succeeded Zeno of Tarsus as the head of the Stoic school at Athens. The most memorable event of his life is the part he took in the embassy which the Athenians sent to Rome in B. C. 155, and which consisted of the three philosophers, Diogenes, Cameades, and Critolaus. These three philosophers, during their stay at Rome, delivered their epideictic speeches at first in numerous private assemblies, and afterwards also in the senate. Diogenes pleased his audience chiefly by his sober and temperate mode of speaking. (Gel. 7.14; Cic. Ac. 2.45; comp. CARNEADES and CRITOLAUS.) According to Lucian (Macrob. 20), Diogenes died at the age of 88; and as, in Cicero's Cato Major (7), Diogenes is spoken of as deceased, he must have died previous to B. C. 151. Diogenes, who is called a great Stoic (magnus et gravis Stoicus, Cic. de Off. 3.12), seems to have closely followed the views of his master, Chrysippus, especially on subjects of dialectics, in which Diogenes is even said to have instructed Carneades. (Cic. Ac. 2.30, de Orat. 2.38.)