This research is concerned with human problem-solving behavior that involves inductive reasoning or concept formation when that behavior is being assisted by certain computer and display aids (called symbol manipulation functions). Human subjects use a variety of systematic operations when they are solving such problems. In order to analyze experimentally these operations and their use, the operations are made available to the problem solver in the form of computer and display aids so that he can implement them quite easily and thereby be relieved of the burden of actually carrying out the details of the operations. Through the complete recording of the use of these computer aids, some aspects of the problem-solving process are externalized for examination. Four specific experiments within this framework utilized three groups of paid subjects who were exposed to two major types of concept problems: classification and relational. The two types call for different kinds of behavior for their successful solution. Rule learning is important for classification problems, while relational problems require rule learning and symbolic manipulation. Aided subjects achieved significantly higher performance on problem-solving than unaided subjects, with the aids proving more useful as problem difficulty increased. Problem-solving ability was transferred both within and between the problem types. (Author/MT)