In vain is the wise man wise, who cannot benefit himself.
 Marcus Tullius Cicero, On Duties (44 BC). copy citation

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Author Marcus Tullius Cicero
Source On Duties
Topic benefit
Date 44 BC
Language English
Reference
Note Translated by Walter Miller
Weblink http://www.constitution.org/rom/de_officiis.htm

Context

“No one could say that this was not the act of an honest man; but people do say that it was not the act of a worldly-wise man, any more than if he had sold for a smaller amount than he could have commanded. Here, then, is that mischievous idea — the world accounting some men upright, others wise; and it is this fact that gives Ennius occasion to say:
In vain is the wise man wise, who cannot benefit himself. And Ennius is quite right, if only he and I were agreed upon the meaning of "benefit."
{63} Now I observe that Hecaton of Rhodes, a pupil of Panaetius, says in his books on "Moral Duty" dedicated to Quintus Tubero that "it is a wise man's duty to take care of his private interests, at the same time doing nothing contrary to the civil customs, laws, and institutions.” source