For all men detest ingratitude and look upon the sin of it as a wrong committed against themselves also, because it discourages generosity
 Marcus Tullius Cicero, On Duties (44 BC). copy citation

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Author Marcus Tullius Cicero
Source On Duties
Topic generosity ingratitude
Date 44 BC
Language English
Reference
Note Translated by Walter Miller
Weblink http://www.constitution.org/rom/de_officiis.htm

Context

“Pains must, therefore, be taken to benefit as many as possible with such kindnesses that the memory of them shall be handed down to children and to children's children, so that they too may not be ungrateful. For all men detest ingratitude and look upon the sin of it as a wrong committed against themselves also, because it discourages generosity; and they regard the ingrate as the common foe of all the poor. Ransoming prisoners from servitude and relieving the poor is a form of charity that is a service to the state as well as to the individual.” source