It may often happen that the untrustworthiness of certain men is completely displayed in a small money matter
 Marcus Tullius Cicero, On Friendship (44 BC). copy citation

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Author Marcus Tullius Cicero
Source On Friendship
Topic money
Date 44 BC
Language English
Reference
Note Translated by E. S. Shuckburgh
Weblink http://www.gutenberg.org/files/2808/2808-h/2808-h.htm

Context

“If we are prudent then, we shall rein in our impulse to affection as we do chariot horses. We make a preliminary trial of horses. So we should of friendship; and should test our friends' characters by a kind of tentative friendship. It may often happen that the untrustworthiness of certain men is completely displayed in a small money matter; others who are proof against a small sum are detected if it be large. But even if some are found who think it mean to prefer money to friendship, where shall we look for those who put friendship before office, civil or military promotions, and political power, and who, when the choice lies between these things on the one side and the claims of friendship on the other, do not give a strong preference to the former?” source