[E]ven though there may be components of well-being that go beyond one’s experiences—and thus can plausibly be thought to come in imperceptible amounts—it seems undeniable that one important component of well-being is indeed the presence of pleasure and the absence of pain.

Shelly Kagan, ‘Do I Make a Difference?’, Philosophy & Public Affairs, Vol. 39, No. 2 (2011), p. 115