What is it to live, as we do, in what Sellars called “the space of reasons”? What are reasons?  Reporting work from a recent book, these lectures explore how reasons show up from the perspectives afforded by different ways of talking about them. The emphasis throughout is on the relational character of reasons: in particular, the relations of implication and incompatibility. These show up as articulating essential norms governing the use of declarative sentences to make claims, underwriting practical assessments of rational defenses of claims, by giving reasons for them, and rational challenges to claims, by giving reasons against them. The same bilateral reason relations show up in a different guise in truth-maker theories of the meaning of declarative sentences. In addition to these pragmatic and semantic vocabularies for talking about reason relations, I consider logical vocabularies for making reason relations explicit (recommending one as the best at that), and introduce a new formal language for talking about and manipulating the conceptual roles sentences come to play by standing in reason relations. Considering the relations among these perspectives on reasons makes visible the outlines of a more perspicuous form of consciousness of ourselves as beings who give and ask for reasons.