MENTAL LIFE OF APES AND MONKEYS 275 
is far from implying that animals cannot perform mental 
operations which are essentially inferential in their nature. 
Reason, as has been stated before, is not a faculty which 
stands sharply marked off from other forms of mental 
activity. Between simple perception on the one hand and 
abstract ratiocination on the other there is a fundamental 
kinship and the latter process may be connected with the 
first by numerous intermediate stages. Monkeys, in all 
probability, have the power of using ideas derived from their 
experience as a means of reaching practical results. The 
monkey which pulls a chair or stool into a certain position, 
gets on it and secures food, manifests a certain power of 
inference. He may not explicitly reason: ‘This fruit is 
beyond my reach; if I had something to get upon I could 
secure the fruit; this chair would serve my purpose and 
moreover is movable; ergo, I will pull it up and get on it.” In 
all probability a man in a similar situation would not reason 
as explicitly either. He would perceive that the object was 
out of his reach; seeing a chair the idea would come of pulling 
it up and getting on it, and the idea would forthwith issue 
in the proper act. There would be no formal syllogism gone 
through with. The process would ordinarily take place 
so quickly that he would scarcely be conscious of the steps. 
It is true that the man might think about the matter in a 
very complex way, and employ a lot of abstract and general 
ideas, but this process would be dispensed with under or- 
dinary conditions, especially if he were in a hurry. The 
man’s mental operations, even in their simplest form, would 
nevertheless be in the nature of an inference, and so far as 
we can judge from appearances, the same statement is true 
of the mind of the monkey. Thelatter cannot, in all proba- 
bility, think the situation over as the man can in terms of a 
formal syllogism, but he has the more immediately useful 
