According to a simple version of the reliability theory of epistemic justification, a belief is justified if and only if the process leading to that belief is reliable. The idea behind this theory is simple and attractive. There are a variety of mental or cognitive processes that result in beliefs. Some of these processes are reliable—they generally yield true beliefs—and the beliefs they produce are justified. Other processes are unreliable and the beliefs they produce are unjustified. So, for example, reliable (...) processes such as perception and memory yield justified beliefs while an unreliable process such as wishful thinking—believing something as a result of wishing that it is true—yields unjustified beliefs. (shrink)

The aim of this paper is to sketch a theory of justified belief. What I have in mind is an explanatory theory, one that explains in a general way why certain beliefs are counted as justified and others as unjustified. Unlike some traditional approaches, I do not try to prescribe standards for justification that differ from, or improve upon, our ordinary standards. I merely try to explicate the ordinary standards, which are, I believe, quite different from those of many classical, (...) e. g., ‘Cartesian’, accounts. (shrink)

Many arguments found in the physics literature involve concepts that are not well-defined by the usual standards of mathematics. I argue that physicists are entitled to employ such concepts without rigorously defining them so long as they restrict the sorts of mathematical arguments in which these concepts are involved. Restrictions of this sort allow the physicist to ignore calculations involving these concepts that might lead to contradictory results. I argue that such restrictions need not be ad hoc, but can sometimes (...) be justified by considering some of the metaphysical issues surrounding the question of the applicability of mathematics to physical reality. 1 Introduction 2 Rejecting inferential permissiveness 3 The agreement problem 4 Independent objections to the liberal view. (shrink)

The dominant response to this problem of the criterion focuses on the alleged requirement that we need to know a belief source is reliable in order for us to acquire knowledge by that source. Let us call this requirement, “The KR principle”.