The happy life is to an extraordinary extent the same as the good life. Professional moralists have made too much of self-denial, and in so doing have put the emphasis in the wrong place. Conscious self-denial leaves a man self-absorbed and vividly aware of what he has sacrificed; in consequence it fails often of its immediate object and almost always of its ultimate purpose. What is needed is not self-denial, but that kind of direction of interest outward which will lead spontaneously and naturally to the same acts that a person absorbed in the pursuit of his own virtue could only perform by means of conscious self-denial.
Source: The Conquest of Happiness, 1930, chap. 17: Th Happy Man.
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