Passionate mutual love while it lasts puts an end to this feeling ; it breaks down the hard walls of the ego, producing a new being composed of two in one. Nature did not construct human beings to stand alone, since they cannot fulfil her biological purpose except with the help of another ; and civilized people cannot fully satisfy their sexual instinct without love. The instinct is not completely satisfied unless a man's whole being, mental quite as much as.physical, enters into the relation.
Source: Bertrand Russell :Marriage and Morals, 1929
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