248 Animal Intelligence 
the behavior of the animal as a whole that seem beyond 
mechanism. By their unmodifiable abandonment of certain 
specific conditions and retention of others, the animal as a 
whole can modify its behavior. Their one rule.of conduct 
causes in him a countless complexity of habits, The learn- 
ing of an animal is an instinct of its neurones. 
I have limited the discussion to animals in ‘whom the con- 
nection-system is a differentiated organ, the neurones. In 
so far as the law of effect operates in an animal whose con- 
nection-system is not anatomically distinguishable and is 
favored and hindered in its life by the same conditions that 
favor and hinder the life of the animal as a whole, the satis- 
fying and annoying will be those states of affairs which the 
connection-system, whatever it be, maintains and abandons. 
The other things that have to be equal in the case of the 
law of effect are: First, the frequency, energy and dura- 
tion of the connection) — that is, the action of the law of ex- 
ercise; second, the closeness with which the satisfaction is 
associated with the response ; and, third, the readiness of the 
response to be connected with the situation. 
The first of these accessory conditions requires no com- 
ment. A slightly satisfying or indifferent response made 
often may win a closer connection than a more satisfying 
response made only rarely. 
The second is most clearly seen in the effect of increasing 
the interval between the response and the satisfaction 
or discomfort. Such an increase diminishes the rate of 
learning. If, for example, four boxes were arranged so that 
turning a button caused a door to open (and permit a cat 
to get freedom and food) in one, five, fifty and five hundred 
seconds, respectively, a cat would form the habit of prompt 
escape from the first box most rapidly and would almost 
certainly never form that habit in the case of the fourth. 
