Affection in the sense of a genuine reciprocal interest for two persons in each other, not solely as means to each other's good, but rather as a combination having a common good, is one of the most important elements of real happiness, and the man whose ego is so enclosed within steel walls that this enlargement of it is impossible misses the best that life has to offer, however successful he may be in his career.
Source: The Conquest of Happiness, 1930, chap.12:Affection.
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