Love, children, and work are the great sources of fertilizing contact between the individual and the rest of the world. Of these love is usually chronologically the first. Moreover, it is essential to the best development of parental affection, since a child is apt to reproduce the characteristics of both parents, and if they do not love each other, each will only enjoy his own characteristics when they appear in the children, and will be pained by the characteristics of the other parent.
Source: Bertrand Russell :Marriage and Morals, 1929
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