Men must always have distinguished (e.g. in judicial matters) between hearsay and seeing with one's own eyes and have preferred what one has seen to what he has merely heard from others. But the use of this distinction was originally limited to particular or subordinate matters. As regards the most weighty matters the first things and the right way the only source of knowledge was hearsay.
Leo StraussAccording to our social science, we can be or become wise in all matters of secondary importance, but we have to be resigned to utter ignorance in the most important respect: we cannot have any knowledge regarding the ultimate principles of our choices, i.e. regarding their soundness or unsoundness... We are then in the position of beings who are sane and sober when engaged in trivial business and who gamble like madmen when confronted with serious issues.
Leo StraussIf the highest things are unknowable, then the highest capacity or virtue of man cannot be theoretical wisdom.
Leo StraussIt is safer to try to understand the low in the light of the high than the high in the light of the low. In doing the latter one necessarily distorts the high, whereas in doing the former one does not deprive the low of the freedom to reveal itself as fully as what it is.
Leo Strauss