Men act unjustly, because it is their interest to do so, and because they prefer their own satisfaction to that of others. They act always to secure some advantage to themselves
 Montesquieu, Persian Letters (1721). copy citation

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Author Montesquieu
Source Persian Letters
Topic satisfaction interest
Date 1721
Language English
Reference
Note Translated by John Davidson
Weblink https://en.wikisource.org/wiki/Persian_Letters

Context

“often indeed, when they do perceive them, they turn aside from them, their own interest being always that which they perceive most clearly. Justice cries aloud; but her voice is hardly heard in the tumult of the passions. Men act unjustly, because it is their interest to do so, and because they prefer their own satisfaction to that of others. They act always to secure some advantage to themselves: no one is a villain gratis; there is always a determining motive, and that motive is always an interested one. But it is not possible that God should ever commit an injustice. As soon as we grant that He perceives what is right, it becomes necessary that He should follow it:” source