To this we answer that the good ruler is a good and wise man, and that he who would be a statesman must be a wise man. And some persons say that even the education of the ruler should be of a special kind; for are not the children of kings instructed in riding and military exercises?
 Aristotle, Politics (4th century BC). copy citation

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Author Aristotle
Source Politics
Topic education rich
Date 4th century BC
Language English
Reference
Note Translated by Benjamin Jowett
Weblink http://classics.mit.edu/Aristotle/politics.html

Context

“I have said enough to show why the two kinds of virtue cannot be absolutely and always the same.
But will there then be no case in which the virtue of the good citizen and the virtue of the good man coincide? To this we answer that the good ruler is a good and wise man, and that he who would be a statesman must be a wise man. And some persons say that even the education of the ruler should be of a special kind; for are not the children of kings instructed in riding and military exercises? As Euripides says:
"No subtle arts for me, but what the state requires. "
As though there were a special education needed by a ruler. If then the virtue of a good ruler is the same as that of a good man, and we assume further that the subject is a citizen as well as the ruler, the virtue of the good citizen and the virtue of the good man cannot be absolutely the same, although in some cases they may; for the virtue of a ruler differs from that of a citizen.” source