Abstract: A standard view of logic is that it is about valid reasoning. In effect, that view reduces logic to metalogic. I will explain how such a view marginalizes more basic roles for logic, in which it both provides knowledge of highly abstract, general, structural principles about the world and articulates scientific hypotheses. I will defend the view that the appropriate methodology for deciding between alternative systems of logic is abductive, favouring such virtues as simplicity, strength, and fit with evidence. Finally, I will show how confusions between logic and metalogic induced by the standard view of logic have led to misapplications of the criterion of strength, thereby obscuring the severe weaknesses of most non-classical logics by comparison with classical logic.
