In general, reasoning in which conclusions can be derived from a set of related premises. More specifically, it entails three main types: deduction (applying a general rule, or major premise, to a specific situation, or minor premise, to arrive at a conclusion, e.g., all humans are mortal, Mick Jagger is human, Mick Jagger is mortal), induction (a specific conclusion is used to determine a general rule, e.g., when the temperature drops below freezing point, Mick Jagger’s open-air swimming pool ices over, today is it below freezing point, Mick Jagger’s open-air swimming pool is covered in ice), abduction (similar to inductive reasoning, but constrained by the application of probabilities, e.g., if it freezes, then Mick Jagger’s open-air swimming pool may ice over). For each of these three types, a distinction can be made between formal and informal reasoning. Formal reasoning, a form of deductive reasoning, is based on valid premises and thus provides a valid set of conclusions. As such, it delivers no new information, but rather ‘rearranges’ what is known into a new conclusion. Informal reasoning, a close cousin of abductive reasoning, takes into account probabilities and truths about premises and conclusions.
See Abstract reasoning, Analogical reasoning, Deduction, Deductive-nomological (D-M) model, Hypothetico-deductive method, Induction (philosophy), Piaget’s stage theory, Problem solving, Reasoning (psychology), Spatial reasoning