Generality and GPS

The General Problem Solver (GPS) is a computer program which has been used for explorations into both general mechanisms involved in problem solving and the way that humans solve problems. The program has existed in several versions since its conception in 1957. This report describes attempts to generalize one version, GPS-2-5; i.e., to have it solve many different kinds of problems. GPS's performance on eleven different tasks is discussed. Several approaches to the construction of a general problem solver are surveyed in order to place GPS in perspective with other approaches and to formulate a meaningful problem of generality. A description of the organization and problem solving techniques of GPS is given, followed by a description of the representation of tasks. The initial need for generalizing the representation of GPS-2-5 stems from the inadequacy of its representation for some tasks. However, the majority of the representational issues investigated in this research are concerned with the interaction between the problem solving techniques of GPS and its representation of tasks. The main consideration in generalizing the representation of GPS-2-5 is that problem solving techniques are applicable only if processes exist that can abstract certain information from the representation of a task.