The truest and most profound observations on Intelligence have in the
past been made by the poets and, in recent times, by story-writers.
They have been keen observers and recorders and reckoned freely with
the emotions and sentiments. Most philosophers, on the other hand,
have exhibited a grotesque ignorance of man's life and have built up
systems that are elaborate and imposing, but quite unrelated to actual
human affairs. They have almost consistently neglected the actual
process of thought and have set the mind off as something apart to be
studied by itself. _But no such mind, exempt from bodily processes,
animal impulses, savage traditions, infantile impressions, conventional
reactions, and traditional knowledge, ever existed_, even in the case
of the most abstract of metaphysicians. Kant entitled his great work
_A Critique of Pure Reason_. But to the modern student of mind pure
reason seems as mythical as the pure gold, transparent as glass, with
which the celestial city is paved.

Formerly philosophers thought of mind as having to do exclusively with
conscious thought. It was that within man which perceived, remembered,
judged, reasoned, understood, believed, willed. But of late it has
been shown that we are unaware of a great part of what we perceive,
remember, will, and infer; and that a great part of the thinking of
which we are aware is determined by that of which we are not conscious.
It has indeed been demonstrated that our unconscious psychic life far
outruns our conscious. This seems perfectly natural to anyone who
considers the following facts:

The sharp distinction between the mind and the body is, as we shall
find, a very ancient and spontaneous uncritical savage prepossession.
What we think of as "mind" is so intimately associated with what we
call "body" that we are coming to realize that the one cannot be