Human beings are so constructed that each sex has much to learn from the other, but mere sex relations, even when they are passionate, do not suffice for these lessons. Co-operation in the serious business of rearing children, and companionship through the long years involved, bring about a relation more important and more enriching to both parties than any that would exist if men had no responsibility for their children.
Source: Bertrand Russell :Marriage and Morals, 1929
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