A great deal of our modern trouble has come from mixing up romantic love, which is a poetic and anarchic impulse, with marriage, which is a social institution. The French have not made this mistake, and on the whole they are considerably happier in these respects than English-speaking nations.
Source: Sex and happiness (written in Aug. 5, 1931 and pub. in Mortals and Others, v.1, 1975.
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