"The merest rudiment of sensation or self-consciousness is infinitely removed from absolutely non-sentient or unconscious matter. We can conceive of no physical addition to, or modification of, an unconscious mass which should create consciousness, no step in the series of changes organized matter may undergo, which should bring sensation where there was no sensation or power of sensation at the preceding step. It is because the things are utterly incomparable and incommensurable that we can only conceive of _sensation_ coming to matter from without, while _life_ may be conceived as merely a specific modification and cooerdination of the matter and the forces that compose the universe, and with which we are separately acquainted. We may admit with Professor Huxley, that _protoplasm_ is the 'matter of life' and the cause of organization; but we cannot admit or conceive that _protoplasm_ is the primary source of sensation and consciousness, or that it can ever of itself become _conscious_ in the same way as we may perhaps conceive that it may become _alive_." Wallace then reaches, without further preliminary discussion, the conclusion that "matter is essentially force" (arguing that we may draw this conclusion from the preceding considerations); that "matter, as popularly understood, does not exist, and is, in fact, philosophically inconceivable. When we touch matter, we only really experience sensations of resistance, implying repulsive force; and no other sense can give us such apparently solid proofs of the reality of matter as touch does." Wallace considers it a great step in advance thus "to get rid of the notion that matter is a thing in itself which can exist _per se_, and must have been eternal, since it is supposed to be indestructible and uncreated,--that force, or the forces of nature, are another thing given or added to matter, or else its necessary properties,--and that mind is yet another thing, either a product of this matter and its supposed inherent forces, or distinct from and co-existent with it"; and to be able to substitute for this theory "the far simpler and more consistent belief, that matter, as an entity distinct from force, does not exist; and that FORCE is a product of MIND."