26 Animal Intelligence 
doning the old method one ought to seek above all to 
replace it by one which will not only tell more accurately 
what they do, and give the much-needed information how. 
they do it, but also inform us what they feel while they act. 
To remedy these defects, experiment must-be substituted 
for observation and the collection of anecdotes. Thus you 
immediately get rid of several of them. You can repeat the 
conditions at will, so as to see whether or not the animal’s. 
behavior is due to mere coincidence. A number of animals 
can be subjected to the same test, so as to attain typical 
results. The animal may be put in situations where its 
conduct is especially instructive. After considerable pre- 
liminary observation of animals’ behavior under various 
conditions, I chose for my general method one which, simple 
as it is, possesses several other marked advantages besides 
those which accompany experiment of any sort. It was 
merely to put animals when hungry in inclosures from which 
they could escape by some simple act, such as pulling at a 
loop of cord, pressing a lever, or stepping ona platform. (A 
detailed description of these boxes and pens will be given 
later.) The animal was put in the inclosure, food was left 
outside in sight, and his actions observed. Besides record- 
ing his general behavior, special notice was taken of how he 
succeeded in doing the necessary act (in case he did succeed), 
and a record was kept of the time that he was in the box 
before performing the successful pull, or clawing, or bite. 
This was repeated until the animal had formed a perfect.: 
‘association between the sense-impression of the interior of 
that box and the impulse leading to the successful movement. 
When the association was thus perfect, the time taken to 
escape was, of course, practically constant and very a 
If, on the other hand, after a certain time the animal did! 
not succeed, he was taken out, but wot fed. If, after a suffi- 
