Competing views

The present account, which construes justification as a kind of epistemic possibility of knowing, or of being in a position to know, competes with three recently advanced theories of justification. Of these competitors, the first two construe doxastic justification as the metaphysical possibility of knowing. While they differ in some details, these views share certain problematic features: they fail to yield a corresponding account of propositional justification, have trouble vindicating an intuitive principle of closure for justified belief, and fail to comply with the independently plausible principle that if one has a justified belief, one is in no position to rule out that one has knowledge. The present account does not have these problematic features. According to the third competitor, |φ‎| is propositionally justified in one’s situation just in case it would be abnormal—and so require explanation—if |φ‎| were to be false in the presence of the evidence that one possesses in that situation. This normic theory of justification validates the principle that propositional justification agglomerates over conjunction, and in so doing, violates the constraint that propositions of the form ⌜φ‎ & ¬Kφ‎⌝ never be justified. It likewise contradicts the independently plausible principle that whenever |φ‎| is propositionally justified all things considered, |¬Kφ‎| is not. The present account does not face these problems, since it rejects the relevant agglomeration principle and treats the condition encoded by ⌜¬K¬Kφ‎⌝ as luminous.