Each person makes an implicit judgment that a life involving donating substantially more would be a life less satisfying than the life that he or she is presently living. Is such a judgment sound? Surely it is for some people, but is it sound on average?

Why allow this distinction? How do you tell, in principle, a person who is actually selfish, from a person who merely incorrectly believes in being selfish, but isn't? Maybe in the "truly selfish" person, the error runs deeper, but is still an error? I'm not so sure that there are any people who lack a whole aspect of value.