138 INTELLIGENT BEHAVIOUR 
second chapter, between the lower or intelligent stage of mental 
development and the higher or rational stage. It will be 
remembered that rational processes were characterized by the 
fact that the situations contain the products of reflective 
thought, presumably absent in the earlier stages of develop- 
ment ; that they were further characterized by a new purpose 
or end of consciousness, namely, to explain the situations which 
at an earlier stage are merely accepted as they are given in 
presentation or re-presentation ; they require deliberate atten- 
tion to the relationships which hold good among the several 
elements of successive situations ; and they involve, so far as 
behaviour is concerned, the intentional application of an ideal 
scheme with the object of rational guidance. 
On the other hand, the animal at the stage of intelligent 
behaviour deals with the circumstances of his comparatively 
simple life by making use of the particular situations which 
have been presented to consciousness in the course of his prac- 
tical experience. If such an animal be placed in the midst of 
new circumstances he has to find out by a process of trial and 
error how they are to be met. After a longer or shorter 
period of trial, guided only by particular experiences, he 
chances to hit upon a mode of procedure which is successful. 
The successful act is then incorporated in a new situation ; at 
first, perhaps, only incompletely.. The association is eventually 
established by repetition, through which is acquired the habit 
of doing the right thing in the appropriate manner. Why he 
does this and not something else, in so far as he is intelligent 
and not rational, he probably neither knows nor has the wit 
to consider. The satisfaction of success suffices for intelligence 
as such. If the circumstances be so modified as to render the 
particular mode of meeting them ineffectual, after trying 
again and again in the old way, he will sometimes stumble 
upon the proper mode of overcoming the difficulty, and after 
doing so two or three times a new conscious situation involving 
the requisite associations will be established, and the appro- 
priate behaviour will become habitual. But why this new 
mode of procedure rather than any other is adopted, intelligence 
