Men being naturally selfish, or endowed only with a confined generosity, they are not easily induced to perform any action for the interest of strangers, except with a view to some reciprocal advantage, which they had no hope of obtaining but by such a performance.
 David Hume, A Treatise of Human Nature (1738). copy citation

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Author David Hume
Source A Treatise of Human Nature
Topic action generosity
Date 1738
Language English
Reference
Note
Weblink http://www.gutenberg.org/files/4705/4705-h/4705-h.htm

Context

“and therefore I venture to conclude that promises are human inventions, founded on the necessities and interests of society. In order to discover these necessities and interests, we must consider the same qualities of human nature, which we have already found to give rise to the preceding laws of society. Men being naturally selfish, or endowed only with a confined generosity, they are not easily induced to perform any action for the interest of strangers, except with a view to some reciprocal advantage, which they had no hope of obtaining but by such a performance. Now as it frequently happens, that these mutual performances cannot be finished at the same instant, it is necessary, that one party be contented to remain in uncertainty, and depend upon the gratitude of the other for a return of kindness.” source