The belly is an ungrateful wretch, it never remembers past favors, it always wants more tomorrow.
Aleksandr Solzhenitsyn, in One Day in the Life of Ivan Denisovich, quoted by Will, who notes that it reminds him of my relationship with food (which he contrasts with his own zen acceptance of the necessity of burritos).
Am I the only one who experiences pangs of fury and despair at the thought that I will never stop having to eat so long as I live? Isn’t it exhausting and exasperating to think that some needs cannot be finally met, that you’re doomed to a Sisyphean struggle with your appetites and urges? The belly wants more tomorrow! It always will, like a spoiled child, never satisfied! More, more, more!
On the other hand: might you rejoice that, unlike our fickle, exhaustible interests, appetites are largely perpetual? Is it comforting that some urges cannot be permanently satiated, since even when we’re bored with everything else, our lives slack and empty and dull, the deep drives to eat and sleep remain, always providing some non-negotiable meaning, however trivial?
What would Sisyphus do without his boulder? Isn’t it amusing that we try to satisfy, and thereby terminate, the desires that animate us? No sooner does some urge enliven us than we want to conclude it. Is this correlated at all to the male sexual experience? Do you find the paradox of desire irritating, depressing, or felicitous?

Quora