ABSTRACT
When a chimpanzee cannot reach an objective hung high up with one box, there is a possibility that he will pile two or more boxes on top of one another and reach it in that way. Whether he actually does this seems a simple question that can soon be decided. But if experiments are made, it is quickly seen that the problem for the chimpanzee falls into two very distinct parts: one of which he can settle with ease, whilst the other presents considerable difficulties. We think the first is the whole problem; where the animal’s difficulties begin, we do not, at first, see any problem at all. If in the description this curious fact is to be emphasized as much as it impressed itself on the observer, the report of the experiment should be divided into two parts in accordance with this fact. I shall begin with the answer to the question that seems to be the only one.
