History teaches us that a given view has been abandoned in favor of another by all men, or by all competent men, or perhaps by only the most vocal men; it does not teach us whether the change was sound or whether the rejected view deserved to be rejected. Only an impartial analysis of the view in question, an analysis that is not dazzled by the victory or stunned by the defeat of the adherents of the view concerned - could teach us anything regarding the worth of the view and hence regarding the meaning of the historical change.
Leo StraussTo avert the danger [posed by theory] to life, Nietzsche could choose one of two ways: he could insist on the strictly esoteric character of the theoretical analysis of life - that is, restore the Platonic notion of the noble delusion - or else he could deny the possibility of theory proper and so conceive of thought as essentially subservient to, or dependent on, life or fate... If not Nietzsche himself, at any rate his successors [Heidegger] adopted the second alternative.
Leo StraussEven by proving that a certain view is indispensable for living well, one proves merely that the view in question is a salutary myth: one does not prove it to be true.
Leo StraussWhen speaking of a "body of knowledge" or of "the results of research," e.g., we tacitly assign the same cognitive status to inherited knowledge and to independently acquired knowledge. To counteract this tendency a special effort is required to transform inherited knowledge into genuine knowledge by revitalizing its original discovery, and to discriminate between the genuine and the spurious elements of what claims to be inherited knowledge.
Leo Strauss