One of the most eminent of psychologists, Clark Hull, claimed that the essence of reasoning lies in the putting together of two 'behavior. segments' in some novel way, never actually performed before, so as to reach a goal. Two followers of Clark Hull, Howard and Tracey Kendler, (21) a test for children that was explicitly based on Clark Hull's principles. The children were given the (22) of learning to operate a machine so as to get a toy. In order to succeed they had to go through a two-stage (23) . The children were trained on each stage (24) . The stages consisted merely of pressing the correct one of two buttons to get a marble and of (25) the marble into a small hole to release the toy. The Kendlers found that the children could learn the separate bits readily enough. (26) the task of getting a marble by pressing the button they could get the marble given the task of getting a toy when a marble was handed to them, they could use the marble. (All they had to do was put it in a hole.) (27) they did not for the most part 'integrate', to use the Kendlers' terminology. They did not press the button to get the marble and then (28) without further help to use the marble to get the toy. So the Kendlers concluded that they were incapable of deductive (29) . The mystery at first appears to deepen when we learn, from (30) psychologist, Michael Cole, and his colleagues, that adults in an African culture apparently cannot do the Kendlers' task either. But it lessens, (31) when we learn that a task was devised which was (32) to the Kendlers' one but much easier for the African males to handle. (33) the button-pressing machine, Cole used a locked box and two (34) colored match-boxes, one of which contained a key that would open the box. Notice that there are still two (35) segments--'open the right matchbox to get the key' and 'use the key to open the box'--so the task seems formally to be (36) But psychologically it is quite different. Now the subject is dealing not with a strange machine but with familiar meaningful objects and it is clear to him what he is meant to do. It then (37) that the difficulty of integration is greatly reduced. Recent work by Simon Hewson is of great interest here for it shows that, for young children, (38) , the difficulty lies not in the (39) processes which the task demands, but in certain perplexing features of the apparatus and the procedure. When these are changed in ways which do not at all affect the inferential nature of the problem, then five-year-old children solve the problem (40) college students did in the Kendlers' own experiments.