General learning ability is a combination of many relatively independent abilities, some of which have not yet been identified and studied experimentally. The acquisition of learning sets, a learning ability which has received considerable attention in the literature, involves the ability to solve single problems, generalize their solutions, transfer such information from one problem to another, and form concepts. Learning set is the acquired ability to solve a particular kind of problem. Discrimination learning set problems have different stimuli but a common basis for solution. The identification by the S of the characteristic which these problems have in common is the discrimination learning set. Harlow (1949) wrote that learning set acquisition depends upon a higher level of thought than is required for single problem learning. The particular set learned determines in large part which stimuli will be generalized in future problem solving
