courage to face all aspects of human behavior from the psycho-
pathologists, it is neither an objective psychology in Bechterew's
sense nor a modified system of psycho-analysis.

The present volume does some violence to the traditional
classification of psychological topics and to their conventional
treatment. For example, the reader will find no discussion of
consciousness and no reference to such terms as sensation, per-
ception, attention, will, image and the like. These terms are in
good repute, but I have found that I can, get along without them
both in carrying out investigations and in presenting psychology
as a system to my students. I frankly do not know what they
mean, nor do I believe that any one else can use them consistently.
I have retained such terms as thinking and memory, but I have
carefully re-defined them in conformity with behavioristic psy-
chology. It is possible to retain attention, to re-define it and
make it serve as a framework for presenting certain aspects both
of the acquisition of any given type of organization and its later
functioning. I have not done so because in an elementary text
the less abstracting of partial functions one can make the better
is the result for the student. Such abstractions are necessary for
pedagogical reasons, but one should strive to get the beginner to
view the organism as a whole as rapidly as possible and to see
in the performance of each and all its acts the working of an
integrated personality. I have tried to do this, but for the sake
of clearness I have clung to the genetic method rather closely
in the hope that if the student could grasp the genesis of the
various types of organization he could put the organism together
for himself. I should like to have had more space to consider the
totally integrated individual in action, but by the time one has
emphasized the necessary part activities, such as instinct, emo-
tions and habits, one has all but exceeded the limits of an elemen-
tary text. Another reason which deters me from enlarging upon
this aspect of psychology is that the discussion of total activity
involves a frankness in dealing with human nature which the
American school public is not yet educated to entertain.

While the nervous system, muscles and glands have been given
somewhat detailed treatment in two chapters, it is realized that

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