Four distinct philosophical schools trace their immediate origin to the circle that gathered round Socrates - the Megarian, the Platonic, the Cynic and the Cyrenaic. The impress of the master is manifest on all, in spite of the wide differences that divide them; they all agree in holding the most important possession of man to be wisdom or knowledge, and the most important knowledge to be knowledge of Good.
He extolled the Cynic luraBeia (loosely, self-control) as the principal virtue.
The closeness of the connexion is illustrated by Juvenal's epigram that a Cynic differed from a Stoic only by his cloak.
Epictetus, however, would have the sage hold aloof from domestic cares, another Cynic trait.
Zeno commenced, then, as a Cynic; and in the developed system we can point to a kernel of Cynic doctrine to which various philosophemes of other thinkers (more especially Heraclitus and Aristotle, but also Diogenes of Apollonia, the Pythagoreans, and the medical school of Hippocrates in a lesser degree) were added.
Finally it is necessary to point out two flaws in the Cynic philosophy.
METROCLES, a Greek philosoper of the Cynic school, was a contemporary of Crates, under whose persuasion he deserted the views of Theophrastus.
This philosopher, a man of striking and attractive personality, succeeded in fusing the Megarian dialectic with Cynic naturalism.
An idea of his writings can be gathered from the fragments of Teles, a cynic philosopher who lived towards the end of the 3rd century, and who made great use of them.
Eubulides wrote a treatise on Diogenes the Cynic and also a number of comedies.