the constant pressure of which we can by no means escape.

Each of these underlying minds has its special sciences and
appropriate literatures. The new discipline of animal or comparative
psychology deals with the first; genetic and analytical psychology
with the second;[10] anthropology, ethnology, and comparative religion
with the third; and the history of philosophy, science, theology, and
literature with the fourth.

We may grow beyond these underlying minds and in the light of new
knowledge we may criticize their findings and even persuade ourselves
that we have successfully transcended them. But if we are fair with
ourselves we shall find that their hold on us is really inexorable. We
can only transcend them artificially and precariously and in certain
highly favorable conditions. Depression, anger, fear, or ordinary
irritation will speedily prove the insecurity of any structure that we
manage to rear on our fourfold foundation. Such fundamental and vital
preoccupations as religion, love, war, and the chase stir impulses
that lie far back in human history and which effectually repudiate the
cavilings of ratiocination.

In all our reveries and speculations, even the most exacting,
sophisticated, and disillusioned, we have three unsympathetic
companions sticking closer than a brother and looking on with jealous
impatience--our wild apish progenitor, a playful or peevish baby, and
a savage. We may at any moment find ourselves overtaken with a warm
sense of camaraderie for any or all of these ancient pals of ours, and
experience infinite relief in once more disporting ourselves with them
as of yore. Some of us have in addition a Greek philosopher or man of
letters in us; some a neoplatonic mystic, some a mediaeval monk, all