Jay Rosenberg offers a systematic philosophical theory of knowledge which is specifically responsive to the fact that we always engage the world from a particular perspective within it. It consequently calls into question in a fundamental way many received understandings regarding the relationships among the concepts of knowledge, belief, justification, and truth. Thinking about Knowing's leading thesis is that we correctly ascribe knowledge to those whom, from our de facto epistemic perspective, we judge able adequately to justify the corresponding belief. Since from any one epistemic perspective the judgments that a person has done everything he needs to do to be entitled to a confident belief, and that he has done everything he needs to do to establish the truth of that belief, stand or fall together, a further 'truth requirement' is vacuous and idle. On this 'perspectivalist' account, unqualified knowledge attributions are always made only from our own epistemic perspective, with reference to a determinate context of inquiry. The theory is consequently both resolutely anti-skeptical and comprehensively fallibilistic. The corresponding 'proceduralist' conception of justification, applying in the first instance to conducts of persons, carries the further 'internalist' consequence that a person's belief is justified only to the extent that he is in a position to justify it.