Full Idea
The moral propositions of Antisthenes foreshadowed the Stoics: virtue can be taught and once acquired cannot be lost (fr.69,71); virtue is the goal of life (22); the sage is self-sufficient, since he has (by being wise) the wealth of all men (8o).
Gist of Idea
Antisthenes said virtue is teachable and permanent, is life's goal, and is like universal wealth
Source
report of Antisthenes (Ath) (fragments/reports [c.405 BCE]) by A.A. Long - Hellenistic Philosophy 1
Book Reference
Long,A.A.: 'Hellenistic Philosophy' [Duckworth 1986], p.7
A Reaction
[He cites Caizzi for the fragments] The distinctive idea here is (I think) that once acquired virtue can never be lost. It sounds plausible, but I'm wondering why it should be true. Is it like riding a bicycle, or like learning to speak Russian?