Induction versus Popper: substance versus semantics.

This article reviews concepts of classical logic and induction, with special attention to the controversies surrounding Popperian claims that induction is impossible and does not exist. I argue that some of the controversy is semantic, and hence Popperian criticisms of induction must be translated carefully into ordinary language to be appreciated by inductively oriented epidemiologists. With this translation, the substance of the debate is not whether induction is possible (it is) or exists (it does), but whether and how we should employ probabilistic reasoning about hypotheses in epidemiological inference.