Deduction, induction, and analogy pervade all our thinking. In contrast with deduction, understanding logical aspects of induction and analogy is still an important and challenging issue of artificial intelligence. This paper describes a logical formalization, called preduction, of common conjectural reasoning of both induction and analogy. By introduction of preduction, analogical reasoning is refined into "preduction + deduction" and (empirical) inductive reasoning is refined into "preduction + mathematical induction". We examine generality of preduction through applications to various examples on induction and analogy.
展开▼