There are two ultimate experiences open to the meditator. Both share in common a contentment and calmness that is supernormal in quality and an absorption in superphysical states. The mystic attains this by religious devotion and the concentration practice alone. But where the latter is accompanied by philosophical discrimination and knowledge, the consciousness is carried almost twice as far into still subtler states and values until it reaches the second ultimate experience. This is near to indescribable, so it has been called "the plane of neither perception nor non-perception." This is because the ego, the conscious observer, is no longer functioning; the experience, the object observed, is no longer there; the residue is a Void. Yet it is not total annihilation; consciousness of some kind must have been held there: for on returning to the normal state, it is picked up again. This raises the interesting question: what, then, is the Void? Ordinarily the term is used for that state where personal, physical, and mental experiences come to a stop but with a rarefied consciousness still remaining. There is no-thing to be known and no-one to know it, certainly no personal memory. This, in the understanding of most students, is the end of the matter: after all, it is too abstract a conception to have any bearing on the lives of those, most of us, who are not monks or hermits with the time and opportunity for prolonged meditations in depth or for intensive analysis of such subtleties. But to complete the record before it is too late, let it be said that there is another kind of Void, seldom studied by the monks and less known among them. In the first kind, there is what might be called "the awareness of awareness." In the second kind, even that ceases. It might be called "death in life." Once experienced, it need not be gone through again, for it leaves its mark permanently on the man. But in the ordinary circumstances of worldly life, especially today, there is little chance for a safe approach to it. Nor is it necessary. For us non-monastic Westerners, the practice of philosophy is the best way.
-- Notebooks Category 23: Advanced Contemplation > Chapter 8: The Void As Contemplative Experience > # 183