Theories of Artificial Intelligence—Meta-Theoretical considerations
Pei Wang · Atlantis thinking machines · 2012
This chapter addresses several central meta-theoretical issues of AI and AGI. After ana-lyzing the nature of the field, three criteria for desired theories are proposed: correctness, concreteness, and compactness. The criteria are clarified in the AI context, and using them, the current situation in the field is evaluated. 1.1. The problem of AI theory Though it is a common practice for a field of science or engineering to be guided and identified by the corresponding theories, the field of Artificial Intelligence (AI) seems to be an exception. After more than half of a century since its formation, AI still has no widely accepted theory, and in the related discussions the following opinions are often heard: • “The best model of intelligence is the human brain itself (and all theories are merely poor approximations...)” • “There is no need for any new theory, since AI can be built according to X (de-pending on who said it, the X can be mathematical logic, probability theory, the-ory of computation,...)” • “A theory of AI has to be established piece by piece, and we are starting from Y (depending on who said it, the Y can be search, reasoning, learning, perception, actions,...)” • “There cannot be any good theory of intelligence (since intelligence is so compli-cated, though our work is obviously central to it...) ” • “Theoretical debating is a waste of time (and we should focus on practical appli-cations. For example, an intelligent system should be able to...)” • “A good theory only comes at the end of the research (so don’t worry about it now, and it will come as long as we continue the current research on...)” There is a historical reason for this situation. Though the idea of “thinking machine” can be traced further back in history, the field of AI was started from the realization that computers, though initially designed to do numerical calculations, can be made to carry out other mental activities, such as theorem proving and game playing, which are hard 1