A high brain may do many things, and may do each of them at a very slight hint. But its hair-trigger organization makes of it a happy-go-lucky, hit-or-miss affair. It is as likely to do the crazy as the sane thing at any given moment. A low brain does few things, and in doing them perfectly forfeits all other use. The performances of a high brain are like dice thrown forever on a table. Unless they be loaded, what chance is there that the highest number will turn up oftener than the lowest?So also the importance of consciousness turned unconscious, a large part of which is culture—and good habits.
Loading its dice would mean bringing a more or less constant pressure to bear in favor of those of its performances which make for the most permanent interests of the brain’s owner; it would mean a constant inhibition of the tendencies to stray aside.
Well, just such pressure and such inhibition are what consciousness seems to be exerting all the while.
— William James, The Principles of Psychology, Vol. I, p.140.