Again, if we say “all pain comes from tension” (_Mind_, xii. p. 6), we have to ask, Tension of what? If we say tension of sensation or ideation, this is Herbartianism merely. How also can tension be felt as painful, except through sensation of tension, which is a feeling of intense sensation—obviously a late psychosis? And certainly pain is more than a general consciousness fatigue. And further stress and strain result in pain, because we imply these as painful activities by the very notion of the words. A stress or strain is assumedly painful activity, but this is not explanation. But apart from this, if the organism felt pain merely as direct result of struggling and straining, it would cease activity; activity and evolution would stop. It may be that by tension is not meant a mode of consciousness, but of nervous or muscular activity; but as we are now considering psychosis only as conditioning pure feeling, we leave this aspect for discussion till a little later. But on the psychical side, that all pain is a by-product of over-intense consciousness, intellectual or volitional, that the origin and development of pain is in a mental intensity which has gone beyond a certain point, this seems, on general evolutionary grounds, unlikely. Here, indeed, is merely a very particular and rather late mode of pain. And may not pains themselves attain an intensity which is itself painful? It must be acknowledged, however, that the whole doctrine as to consciousness intensity, its nature, reactions, laws, and measurements is very obscure. Again, as to the theory that pleasure-pain is reflex of quantity of consciousness, that pleasure results from mental expansion, pain from mental contraction, this must, like the intensity theory, be considered as putting a late and special form as covering all forms. Mentality here exists for itself, and conscious self-development—a very late mode—is presupposed. The promotion of large complete free consciousness, the sense of progress and of unimpeded mental activity, certainly conveys high joys to certain choice natures, but they do not touch the vast majority of even human minds, much less animal. With the stolid an expanding consciousness is painful. Consciousness only as conscious of itself, and as self-developing, reaches a pleasure or pain as a felt furtherance or hindrance of its own expansion.