In fact the whole antithesis between self and the rest of the world, which is implied in the doctrine of self-denial, disappears as soon as we have any genuine interest in persons or things outside ourselves. Through such interests a man comes to feel himself part of the stream of life, not a hard separate entity like a billiard-ball, which can have no relation with other such entities except that of collision.

Bertrand Russell (1872-1970) English mathematician and philosopher

Conquest of Happiness, Part 2, ch. 17 “The Happy Man” (1930)
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