But we may say more: an inquiry into their nature is absolutely necessary. First, because we maintained that Moral Virtue and Moral Vice are both concerned with Pains and Pleasures: next, because the greater part of mankind assert that Happiness must include Pleasure …. Now some hold that no one Pleasure is good, either in itself or as a matter of result, because Good and Pleasure are not identical. Others that some Pleasures are good but the greater number bad. There is yet a third view; granting that every Pleasure is good, still the Chief Good cannot possibly be Pleasure.
– Aristotle, Nicomachean Ethics