CLOUD OF UNKNOWING
A famous treatise on mystical prayer, variously attributed to Walter Hilton (d. 1396) an English mystic, to an unknown contemplative monk and to the Carthusians. Its theme is that God cannot be known by reason and that there is a cloud of unknowing in the affections. Contemplative prayer is said to be not in the intellectual but in the volitional and affective part of man and therefore necessarily contains an element of ignorance. As the author explains, the work is not meant for beginners but for those already advanced in the spiritual life.