Abstract

The sense in which having the available belief that P gives one a reason for believing that one believes that P is just that if one has that available belief one is thereby justified, or warranted, in believing that one has it. In explaining why it is so it helps to bring in the notion of rationality. We noted earlier that it is a requirement of full human rationality that one regularly revise one’s belief system in the direction of greater consistency and coherence, and, as a condition of one’s being able to do this, that one have access to its contents and their relations to one another. Judging that one believes something when one does, and judging that one doesn’t believe something when one doesn’t, are manifestations of the satisfaction of this requirement of rationality. That seems a sufficient reason to say that one is warranted in doing so.