58. There remains yet that part of the argument which hints that individual consciousness is less permanent than matter, inasmuch as such consciousness frequently departs from the universe for six or eight hours and then returns to it again. In one sense this is unquestionably true, while, however, there is a potential or latent consciousness or possibility of consciousness that remains behind.[29] It will be seen in the sequel that this fact of latent consciousness will be used by us to strengthen our argument in favour of a future state. 59. We may conclude, as the result of this discussion, that the connection between mind and matter is a very intimate one, although we are in profound ignorance as to its exact nature. The intimacy of this connection is a doctrine almost universally held by modern physiologists. Just as no single action of the body takes place without the waste of some muscular tissue, so, it is believed, no thought takes place without some waste of the brain. Nay, physiologists go even further, and assert that each specific thought denotes some specific waste of brain matter, so that there is some mysterious and obscure connection between the nature of the thought and the nature of the waste which it occasions. In like manner memory is looked upon as dependent upon traces, left behind in the brain, of the state in which it was when the sensation remembered took place. Thus Professor Huxley in his Belfast address (1874) tells us: ‘It is not to be doubted that those motions which give rise to sensation leave on the brain changes of its substance which answer to what Haller called “_vestigia rerum_,” and to what that great thinker David Hartley termed “Vibratiuncules.” The sensation which has passed away leaves behind molecules of the brain competent to its reproduction—“sensigenous molecules,” so to speak—which constitute the physical foundation of memory.’ 60. It will be inferred from what we have said that one of the essential requisites of continued existence of the individual is the capability of retaining some sort of hold upon the past: and, inasmuch as we are unable to contemplate such a thing as a finite disembodied spirit, or, to speak more precisely, an unconditioned finite spirit, it is further evident that this hold implies an organ of some sort. This we conceive to be a perfectly general proposition. We do not limit ourselves in making it to any particular arrangement of bodily form, or to any particular rank of finite organised intelligence. From the archangel to the brute we conceive that something analogous to an organ of memory must be possessed by each. This is, in fact, merely a corollary to what has been stated in Art. 54 above, and does not require any further discussion.