nction;
otherwise the vital needs of individual and race might be suppressed
by other interests, and neglected. In the case of the sexual instinct,
the mutual relations between the various parts of this circulatory
process are especially complicated. Here it must be sufficient to say
that the idea of sexual processes produces dilation of blood vessels
in the sexual sphere, and that this physiological change itself
becomes the source and stimulus for more vivid sexual feelings, which
associate themselves with more complex sexual thoughts. These in their
turn reinforce again the physiological effect on the sexual organ, and
so the play goes on until the irritation of the whole sexual apparatus
and the corresponding sexual mental emotions reach a height at which
the desire for satisfaction becomes stronger than any ordinary motives
of sober reason.

This is the great trick of nature in its incessant service to the
conservation of the animal race. Monogamic civilization strives to
regulate and organize these race instincts and to raise culture above
the mere lure of nature. But that surely cannot be done by merely
ignoring that automatic mechanism of nature. On the contrary, the
first demand of civilization must be to make use of this inborn
psychophysical apparatus for its own ideal human purposes, and to
adjust the social behaviour most delicately to the unchangeable
mechanism. The first demand, accordingly, ought to be that we excite
no one of these mutually reinforcing parts of the system, neither the
organs nor the thoughts nor the feelings, as each one would heighten
the activities of the others, and would thus become the starting point
of an irrepressible demand for sexual satisfaction. The average boy or
girl cannot give theoretical attention to the thoughts concerning
sexuality without the whole mechanism for reinforcement automatically
entering into action. We may instruct with the best intention to
suppress, and yet our instruction itself must become a source of
stimulation, which necessarily creates the desire for improper
conduct. The policy of silence showed an instinctive understanding of
this fundamental situation. Even if that traditional policy had had no
positive purpose, its negative function, its leaving at rest the
explosive sexual system of the youth, must be acknowledged as one of
those wonderful instinctive procedures by which society protects
itself.

The reformer might object that he gives not