The more things a man is interested in, the more opportunities of happiness he has, and the less he is at the mercy of fate, since if he loses one thing he can fall back upon another. Life is too short to be interested in everything, but it is good to be interested in as many things as are necessary to fill our days. We are all prone to the malady of the introvert, who, with the manifold spectacle of the world spread out before him, turns away and gazes only upon the emptiness within.

Bertrand Russell (1872-1970) English mathematician and philosopher

Conquest of Happiness, Part 2, ch. 11 “Zest” (1930)
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