Happy Thanksgiving for those in the United States.
I continue to maintain that Thanksgiving is the most Epicurean of the secular holidays. Gratitude plays such a large role in Epicurus' philosophy that already having an established holiday in the culture is a convenient bonus. While Epicureans have a Twentieth every month, Thanksgiving is a time already in the calendar that brings together friends and family and provides an opportunity to reflect on what we can be grateful for.
A selection:
VS35. Don't ruin the things you have by wanting what you don't have, but realize that they too are things you once did wish for.
VS55. Misfortune must be cured through gratitude for what has been lost and the knowledge that it is impossible to change what has happened.
U423 Epicurus too makes a similar statement to the effect that the good is a thing that arises out of your very escape from evil and from your memory and reflection and gratitude that this has happened to you. (Plutarch)
U435 Seneca, On Benefits, III.4.1: Here I must do Epicurus the justice to say that he constantly complains of our ingratitude for past benefits, because we cannot bring back again, or count among our present pleasures, those good things which we have received long ago, although no pleasures can be more undeniable than those which cannot be taken from us.
U491 Seneca, Letters to Lucilius, 15.10: … a striking maxim that comes from Greece – here it is: "The life of folly is empty of gratitude and full of anxiety – it is focused wholly on the future." "Who said that?" you ask. The same man as before. {Epicurus}
U592 Diogenes Laertius, Lives of Philosophers, X.121: He will be grateful to anyone when he is corrected.
U469 Johannes Stobaeus, Anthology, XVII.23: "Thanks be to blessed Nature because she has made what is necessary easy to supply, and what is not easy unnecessary."