Let us acknowledge then that each one has just so much of happiness as he has of virtue and wisdom, and of virtuous and wise action. God is a witness to us of this truth, for he is happy and blessed, not by reason of any external good, but in himself and by reason of his own nature.
 Aristotle, Politics (4th century BC). copy citation

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

Context

“Again, it is for the sake of the soul that goods external and goods of the body are eligible at all, and all wise men ought to choose them for the sake of the soul, and not the soul for the sake of them.
Let us acknowledge then that each one has just so much of happiness as he has of virtue and wisdom, and of virtuous and wise action. God is a witness to us of this truth, for he is happy and blessed, not by reason of any external good, but in himself and by reason of his own nature. And herein of necessity lies the difference between good fortune and happiness; for external goods come of themselves, and chance is the author of them, but no one is just or temperate by or through chance.” source