Metareasoning: A Manifesto

The 21st century is experiencing a renewed interest in an old idea within artificial intelligence that goes to the heart of what it means to be both human and intelligent. This idea is that much can be gained by thinking about one's own thinking. Traditionally within cognitive science and artificial intelligence, thinking or reasoning has been cast as a decision cycle within an actionperception loop similar to that shown in Figure 1. An intelligent agent perceives some stimuli from the environment and behaves rationally to achieve its goals by selecting some action from its set of competencies. The result of these actions at the ground level is subsequently perceived at the object level and the cycle continues. Metareasoning is the process of reasoning about this reasoning cycle. It consists of both the meta-level control of computational activities and the introspective monitoring of reasoning (see Figure 2). This cyclical arrangement represents a higher-level reflection of the standard action-perception cycle, and as such, it represents the perception of reasoning and its control.