Gratitude (Stanford Encyclopedia of Philosophy)

3.2 Affective Elements

Most philosophers agree that in addition to certain beliefs, gratitude calls for certain feelings or affects in a beneficiary, without which he fails to count as grateful.

One notable exception is Hichem Naar (2019), who argues that mere grateful beliefs, unaccompanied by feelings, can constitute a shallow kind of gratitude he calls “generic gratitude”, typically appropriate in response to trivial favors.

Even Naar, however, acknowledges that “deep gratitude” includes certain feelings.

https://plato.stanford.edu/entries/gratitude/#CogEle