Attempts to define mystical experience have been as diversified and as conflicting as attempts to interpret and assess its significance. This is not surprising, for the language used to express and describe mystical experience is richly paradoxical, figurative, and poetical. Even if at times a mystic chooses what look like austere and precise metaphysical terms, this may be only an apparent concession to logic, for he will employ these terms in senses far from normal. Mystics have called the Godhead a sheer "Nothing" and yet the ground of all. They have affirmed simultaneously that the world is identical with God and that the world is not identical with God.

Some discriminations are possible, even if exact definition is not. Mystical experience is religious experience, in a broad but meaningful sense of "religious." It is sensed as revealing something about the...