What Do We Owe After Receiving Help?

A friend spends an entire day helping you move house. Months later, they ask you to support an expense claim you know is false. Does the earlier help mean you now owe them this favour? We readily say that kindness deserves gratitude, but it is less clear what obligation gratitude creates.

In Question 106 of the Second Part of the Second Part of the Summa Theologiae, Aquinas argues that the moral character of a benefit depends chiefly on the giver's will. A grateful response is not simply the return of an equal object. It must consider goodwill, timing, the recipient's capacity and the benefactor's need. He even says that a repayment should not be made mechanically when it would be harmful or useless to the person receiving it. A “debt of gratitude” therefore differs from a contractual debt that can be settled to an exact amount.

Contemporary philosophy still disputes whether gratitude is primarily an emotion, a virtue or a source of special duties to a benefactor. One difficulty is that a benefactor who uses past help to control someone turns a gift into a transaction whose price was disclosed only afterwards. My judgement is that genuine help gives the recipient reasons to acknowledge goodwill, express thanks and, when appropriate, give some priority to the benefactor's reasonable needs. Those reasons have limits. They cannot require lying, harming a third party or surrendering basic autonomy. Help with moving can support helping the friend in a future need; it cannot make false testimony right. Gratitude preserves goodwill in a relationship. It does not turn the recipient into property.

https://www.newadvent.org/summa/3106.htm
https://plato.stanford.edu/entries/gratitude/