Antisthenes of Athens | Diogenes Laertius, Book 1 §19

<blockquote>The founders of these schools were: of the Old Academy, Plato; of the Middle Academy, Arcesilaus; of the New Academy, Lacydes; of the Cyrenaic, Aristippus of Cyrene; of the Elian, Phaedo of Elis; of the Megarian, Euclides of Megara; of the Cynic, Antisthenes of Athens; of the Eretrian, Menedemus of Eretria; of the Dialectical school, Clitomachus of Carthage; of the Peripatetic, Aristotle of Stagira; of the Stoic, Zeno of Citium; while the Epicurean school took its name from Epicurus himself.

Hippobotus in his work On Philosophical Sects declares that there are nine sects or schools, and gives them in this order: (1) Megarian, (2) Eretrian, (3) Cyrenaic, (4) Epicurean, (5) Annicerean, (6) Theodorean, (7) Zenonian or Stoic, (8) Old Academic, (9) Peripatetic. He passes over the Cynic, Elian, and Dialectical schools.

Source: Lives of the Eminent Philosophers (1925) by Diogenes Laërtius, translated by Robert Drew Hicks. A Loeb Classical Library edition; volume 1 published 1925; volume 2 published 1925. WikiSource.
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