Communication and Language: An Evolutionary View

COMMUNICATION AND LANGUAGE: AN EVOLUTIONARY VIEW Lewis Petrinovichl A parable of sticks. Once, not so long ago, some wise men were asked to explain how animals solve problems. It was agreed that the chimpanzee was an animal worthy of consideration and that a good problem would be to have a chimpanzee find a stick and use the stick to reach a banana outside arm's reach from the cage where the chimp was kept. The first wise man (Khler 1927) was European and of a contemplative, philosophical bent. He began by watching the chimp try to get the banana and observed the chimp's attempts at a variety of direct solutions. All of these tries were unsuccessful , of course, since it had been arranged that simple, direct solutions wouldn't work. Sometimes the chimp engaged in idle fiddling with the stick, and sometimes this fiddling was followed by a sudden, successful use of the stick as a tool to fetch the banana. This led our wise man to propound an explanation that emphasized the insightful nature of problem solving and to speculate whether such insightful learning was characteristic of problem solving in general. He concluded that it most probably was, and he then thought about the marvels of what went on inside the chimp's head when it discerned the critical structural elements of the situation and suddenly attained the "aha" experience--with the banana following closely behind. We leave this wise man speculating on the nature of the phenomenological and physical processes desporting themselves in the head of the chimp. He speaks little of chimps, of bananas, or of sticks but mainly about inferred central processes. 1The preparation of this manuscript was supported by Research Grant HD-04343 from the National Institute of Child Health and Human Development. Sign Language Studies 13 A second wise man (Thorndike 1911) was of a different persuasion; he watched the chimp try to get the banana and decided that the chimp tried this and that until finally something or other worked and got the banana. So, he decided, a desiring chimp moves about trying to get the banana, and, after much trial and error, it lucks into the way to obtain the goal--it pulls the banana in with the stick. The movements the chimp makes which lead to the banana--a positive state of affairs--would be more likely to occur on the next occasion, and the chimp would get the banana even faster than it did the first time. Why did the solution observed by the first wise man seem to be so sudden and insightful? Because the chimp had had experience in its remote past with things like sticks and bananas and had come to associate certain movements with the attainment of reward--so said the second wise man's colleagues (Birch 1945). This led the second wise man to the conclusion that to understand how animals solve problems it is necessary to understand the movement patterns that have been rewarded and punished in the past life of the beast. Thus, he explained to the first wise man, the insight phenomenon could be understood completely by careful analysis of the past movements of the chimp in relation to sticks and bananas. This second wise man concerned himself no more with the chimp, the banana, or the stick but proceeded to study the movements of chimp hands, arms, and nervous systems to discover the general laws by which movements were chained together to attain rewards and to avoid punishments. A third wise man (Skinner 1938) decided that all this talk of why and how the chimp got the banana that had occupied the first two wise men was not at all relevant to the question. All of this previous talk involved something other than the behavior of the chimp; and our third wise man wanted to avoid talk of vague, nonobservable things going on inside the skin of the chimp, especially those things which lived inside the chimp's head; and he didn't wish to concern himself with small patterns of movement either. He proposed instead to focus on the stick. To do this he created an environment in which...