CHAPTER VII 
THE NON-INTELLIGENT MODIFICATIONS OF 
BEHAVIOR 
“Both elements, automatism and plasticity, are found in different 
proportions with all animals from the highest to the lowest.”— 
WasMann, Psychology of Ants and of Higher Animals. 
While there is in all organisms a certain measure of useless 
if not positively injurious activity, the organic mechanism 
is a self regulating one, and meets varied conditions of 
life with appropriate changes of response. These adaptive 
changes in relation to different circumstances are found even 
in the lowest organisms. With the evolution of life they be- 
come more varied and more specialized and contribute to the 
development of intelligence which may be regarded as but 
one species of the comparatively large genus of adaptive 
variation of behavior. In accordance with a common 
usage the term intelligence is here restricted to those forms 
of behavior based upon the formation of associations. 
As Spencer has shown, intelligence is a part of the general 
process of adjustment which makes up the behavior of an 
animal. To a certain extent behavior is stereotyped and 
to a certain extent it is plastic. Both kinds of behavior are 
necessary in varying degrees in the life of all animals. In 
this chapter we shall consider some of the plastic features 
of behavior in which the element of association is not involved. 
ACTION OF COMBINED STIMULI 
Reaction to any given stimulus is often interfered with by 
a tendency to react to other stimuli received at the same 
139 
