ABSTRACT
Beliefs are the “stuff” of reasoning: they are what reasoning produces and the basis on which reasoning is done. Belief is assumed to be an intuitively meaningful concept. Given the central role that beliefs play in our lives, effective reasoning requires both an awareness that our beliefs are indeed beliefs and a desire to make those beliefs consistent with whatever relevant evidence is available. Effective reasoning demands a continuing effort to make the strength of any belief commensurate with the weight of evidence in its favor. The chapter discusses several aspects of beliefs and their importance to reasoning. The distinction between beliefs and opinions can serve a useful purpose, even though there may be instances that are difficult to classify unambiguously as either the one or the other.
