Abstract

David Hume’s “Title Principle,” as it has come to be called, is a specification of the normative scope of reason: “Where reason is lively, and mixes itself with some propensity, it ought to be assented to. Where it does not, it never can have any title to operate on us.” This chapter seeks to answer four central questions about the principle. First, what does Hume mean by “reason” in it? Second, what particular kinds of beliefs does it mandate or disallow? Third, what kind of normativity is expressed by its use of “ought”? Fourth, can it permit Hume properly to overcome—if only to some extent—the “doubts,” “contradictions and imperfections,” and “objections” concerning the use of reason that he describes prior to stating the principle? The chapter concludes with brief reflections on the significance for contemporary epistemology of Hume’s use of the Title Principle.