nct (aided, of course, by other extraneous
causes) has hardened into custom; and there is reason to believe (from
the universal traces among the higher civilisations of marriage by
capture) that all the leading races of the world are ultimately derived
from exogamous ancestors, possessing this healthy and excellent
sentiment.

In minor matters, it is of course universally admitted that short men,
as a rule, prefer tall women, while tall men admire little women. Dark
pairs by preference with fair; the commonplace often runs after the
original. People have long noticed that this attraction towards one's
opposite tends to keep true the standard of the race; they have not,
perhaps, so generally observed that it also indicates roughly the
existence in either individual of a desire for its own natural
complement. It is difficult here to give definite examples, but
everybody knows how, in the subtle psychology of Falling in Love, there
are involved innumerable minor elements, physical and mental, which
strike us exactly because of their absolute adaptation to form with
ourselves an adequate union. Of course we do not definitely seek out
and discover such qualities; instinct works far more intuitively than
that; but we find at last, by subsequent observation, how true and how
trustworthy were its immediate indications. That is to say, those men do
so who were wise enough or fortunate enough to follow the earliest
promptings of their own hearts, and not to be ashamed of that divinest
and deepest of human intuitions, love at first sight.

How very subtle this intuition is, we can only guess in part by the
apparent capriciousness and incomprehensibility of its occasional
action. We know that some men and women fall in love easily, while
others are only moved to love by some very special and singular
combination of peculiarities. We know that one man is readily stirred by
every pretty face he sees, while another man can only be roused by
intellectual qualities or by moral beauty. We know that sometimes we
meet people possessing every virtue and grace under heaven, and yet for
some unknown and incomprehensible reason we could no more fall in love
with them than we could fall in love with the Ten Commandments. I don't,
of course, for a moment accept the silly romantic notion that men and
women fall in love only once in their lives, or that each one of us has
somewhere on earth his or her exact affinity, whom we must sooner or
later