Experimental Reason

'Deduction' can be defined as a relation between a universal proposition and an instance, and 'induction' as that between a multiplicity of individual propositions and a general one.  An inference that is an alternative to both of these--from a single arbitrary individual proposition to a universal one--is recognized as 'universal generalization' in contemporary Predicate Logic. Such reasoning is involved in most mathematical and geometrical demonstrations, in which a proof pertaining to the properties of a single example suffices for all cases.  Kant's insight, developed in the B edition preface to the 1st Critique, is that the same inference is involved in experimental logic, i. e. in which the results of a single experiment, e. g. Galileo's experiment with balls rolling down a plane to show that they accelerate, suffices for all cases.  His explanation for the validity of such an inference is that it entails Reason recognizing its own contribution to phenomena, and, hence, as entailing a prior knowledge.