David Cooper explores and defends the view that a reality independent of human perspectives is necessarily indescribable, a "mystery." Other views are shown to be hubristic. Humanists, for whom "man is the measure" of reality, exaggerate our capacity to live without the sense of an independent measure. Absolutists, who proclaim our capacity to know an independent reality, exaggerate our cognitive powers. In this highly original book Cooper restores to philosophy a proper appreciation of mystery-that is what provides a measure of our beliefs and conduct.