Abstract

Distinguishes five different kinds of rationality that a belief may possess. It may be rational in being probable, given the believer's evidence and his inductive standards; or probable, given the believer's evidence and correct inductive standards. Or it may be rational in being the result of what the believer regards as adequate investigation, or the result of adequate investigation by the believer's own standards, or the result of adequate investigation by correct standards. Correct standards require a subject to investigate the truth of a proposition; insofar as its initial probability is not very close to l or 0, there is an initial probability that investigation will change the probability, and having a true belief on the issue is important relative to other demands on the subject's time.