for example, and especially sensation.

There would be objection also from the side of psychology, which does
not wish to limit itself to conscious action. Take the case of any act
that can at first be done only with close attention, but that becomes
easy and automatic after practice; at first it is conscious, later
unconscious, but psychology would certainly need to follow it from the
initial to the final stage, in order to make a complete study of the
practice effect. And then there is the "unconscious", or the
"subconscious mind"--a matter on which psychologists {8} do not wholly
agree among themselves; but all would agree that the problem of the
unconscious was appropriate to psychology.

For all the objections, it remains true that the _typical_ mental
process, the typical matter for psychological study, is conscious.
"Unconscious mental processes" are distinguished from the unconscious
activity of such organs as the liver by being somehow _like_ the
conscious mental processes.

It would be correct, then, to limit psychology to the study of
conscious activities and of activities akin to these.

The Science of Behavior

No one has objected so strenuously to defining psychology as the
science of consciousness, and limiting it to consciousness, as the
group of animal psychologists. By energetic work, they had proved that
the animal was a very good subject for psychological study, and had
discovered much that was important regarding instinct and learning in
animals. But from the nature of the case, they could not observe the
consciousness of animals; they could only observe their behavior, that
is to say, the motor (and in some cases glandular) activities of the
animals under known conditions. When then the animal psychologists
were warned by the mighty ones in the science that they must interpret
their results in terms of consciousness or not call themselves
psychologists any longer, they rebelled; and some of the best fighters
among them took the offensive, by insisting that human psychology, no
less than animal, was properly a study of behavior, and that it had
been a great mistake ever to define it as the science of
consciousness.

It is a natural assumption that animals are conscious, but after all
you cannot directly observe their consciousness, and you cannot
logically confute those philosophers {9} who have contended that the
animal was an unconscious automaton. Still less can you be sure in
detail w