The Yogis have always taught that the mind has many planes of manifestation and action--and that many of its planes operated above and below the plane of consciousness. Western science is beginning to realize this fact, and its theories regarding same may be found in any of the later works on psychology. But this is a matter of recent development in Western science. Until very recently the text books held that Consciousness and Mind were synonymous, and that the Mind was conscious of all of its activities, changes and modifications. Liebnitz was one of the first Western philosophers to advance the idea that there were planes of mental activity outside of the plane of consciousness, and since his time the leading thinkers have slowly but surely moved forward to his position. At the present time it is generally conceded that at least ninety per cent of our mental operations take place in the out-of-conscious realm. Prof. Elmer Gates, the well known scientist, has said: "At least ninety per cent of our mental life is sub-conscious. If you will analyze your mental operations you will find that conscious thinking is never a continuous line of consciousness, but a series of conscious data with great intervals of subconscious. We sit and try to solve a problem, and fail. We walk around, try again, and fail. Suddenly an idea dawns that leads to the solution of the problem. The subconscious processes were at work. We do not volitionally create our own thinking. It takes place in us. We are more or less passive recipients. We cannot change the nature of a thought, or of a truth, but we can, as it were, _guide the ship by a moving of the helm_. Our mentation is largely the result of the great Cosmic Whole upon us." Sir William Hamilton says that the sphere of our consciousness is only a small circle in the center of a far wider sphere of action and thought, of which we are conscious through its effects. Taine says: "Outside of a little luminous circle, lies a large ring of twilight, and beyond this an indefinite night; but the events of this twilight and this night are as real as those within the luminous circle."