Wayne Sumner

[T]here are quite commonplace instances of our not being averse to, or even relishing, pain. I can deliberately probe a loose tooth with my tongue and find the sharp pang which results quite delicious. In this case I have no difficulty identifying the feeling as painful; indeed, that seems to be part of its appeal.

Wayne Sumner, Welfare, Happiness, and Ethics, Oxford, 1996, p. 101