“A perfect man would never act from a sense of duty; he’d always want the right thing more than the wrong one. Duty is only a substitute for love (of God and of other people) like a crutch which is a substitute for a leg. Most of us need the crutch at times; but of course it is idiotic to use the crutch when our own legs (our own loves, tastes, habits, etc.) can do the journey on their own.”
—C.S. Lewis, Letters, 18 July 1957.