When we look round the world at the present day and ask ourselves what conditions seem on the whole to make for happiness in marriage and what for unhappiness, we are driven to a somewhat curious conclusion : that the more civilized people become the less capable they seem of lifelong happiness with one partner. ... When a man differs little from other men, and a woman differs little from other women, there is no particular reason to regret not having married someone else. But people with multi-farious tastes and pursuits and interests will be apt to desire congeniality in their partners, and to feel dissatisfied when they find that they have secured less of it than they might have obtained.
Source: Bertrand Russell :Marriage and Morals, 1929
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