Contempt for happiness is usually contempt for other people’s happiness, and is an elegant disguise for hatred of the human race.

Russell is criticizing a posture of world-weary superiority that dismisses “happiness” as shallow or unworthy. He suggests that such disdain is rarely a purely personal ascetic ideal; more often it is directed outward, resenting the ordinary satisfactions of others. In that sense, contempt for happiness becomes a social and moral attitude: it denies the legitimacy of human needs and pleasures, and can function as a refined mask for misanthropy. The “elegant disguise” phrase implies that intellectual or aesthetic sophistication can be used to launder hostility into something that looks principled. Russell’s broader ethical outlook treats happiness as a serious human good, so scorning it is, for him, a symptom of alienation rather than wisdom.