The Enlightenment conferred great authority upon its tribunal of criticism. The principle of sufficient reason suffered no exceptions; all beliefs had to submit to its requirements. Nothing was sacred before the criticism of reason, not even the state in its majesty nor religion in its holiness.. Nothing, that is, except of course the tribunal of critique itself, which was somehow sacred, holy and sublime.
But such a conspicuous and dubious exception only created suspicions about the Enlightenment faith in criticism. Some philosophers began to recognize that an unqualified demand for criticism is self-reflexive, applying to reason itself. If it is the duty of reason to criticize all our beliefs, then ipso facto it must criticize itself; for reason has its own beliefs about itself, and these cannot escape criticism. To refuse to examine these beliefs is to sanction ‘dogmatism’, the demand that we accept beliefs on trust. But dogmatism, which refuses to give reasons, is clearly the chief enemy of criticism, which demands that we give reasons. So, unless criticism is to betray itself, it must become, in the end, meta-criticism, the critical examination of criticism itself.
Yet if the meta-criticism of reason is necessary, is it not also dangerous? If reason must criticize itself, then it must ask the question, ‘How do I know this?’ or ‘What reason do I have to believe this?’ But then we seem to face a very disturbing dilemma. Either we must ask this question ad infinitum, and embrace skepticism, or we must refuse to answer it, and lapse into dogmatism.- Frederick C. Beiser, The Fate of Reason, page 6.