Love, when the word is properly used, does not denote any and every relation between the sexes, but only one involving considerable emotion, and a relation which is psychological as well as physical. It may reach any degree of intensity. ... It is much commoner in some societies than in others, and this depends, I think, not upon the nature of the people concerned but upon their conventions and institutions.
Source: Bertrand Russell :Marriage and Morals, 1929
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