If, now, the knowledge of the connection of the elements (sensations) does not suffice us, and we must ask Who, What, possesses this connection of sensations, Who, What, perceives sensations? we have succumbed, we may be sure, to our old habit of arranging every element (every sensation) within some unanalysed complex, and we are falling back imperceptibly to an older, lower, and more limited point of view.
* * * * *
The habit of treating the unanalysed ego-complex as an indivisible unity is often scientifically presented in peculiar ways. First, the nervous system is separated from the body as the seat of sensations. In the nervous system again the brain is selected as fitted for the performance of this function, and finally, to save the pretended psychical unity, a further point is sought in the brain as the seat of the soul. But rough conceptions like these are hardly adapted to trace out even in the crudest lines the ways that future research will follow in investigating the connection of the physical and the psychical. The fact that the different organs of sensation and memory are physically connected with one another, and can be easily excited by one another is probably the foundation of the "psychical unity."
I once heard the question seriously discussed of "How the percept of a very large tree found room in the little head of a man?" Now though this "problem" does not exist, yet we perceive by the question the absurdity that is so easily committed in conceiving sensations to exist spacially in the brain. When I speak of the sensations of another person, these sensations of course present no activity in my optical space or my physical space generally; they are mentally added, and I conceive them to be causally annexed, not spacially, to the brain observed or represented. When I speak of my sensations, these sensations do not exist spacially in my head, but rather my "head" shares with them the same spacial field, as was explained above (compare what was said regarding the cut).
* * * * *
Let there be no mention of the so-called unity of consciousness. Since the apparent opposition of the real and the perceived world exists only in the mode according to which it is viewed, and no real chasm exists, a multiplex interconnected content of consciousness is in no respect more difficult to understand than the multiplex interconnection of the world.
If we are determined to regard the ego as an actual unity, we cannot extricate ourselves from the following dilemma: either to set over against it—viz., the ego—the world of incognisable substances (which would be wholly idle and purposeless), or to regard the whole world, the egos of other people included, as only contained in our own ego (to which, seriously, we could hardly make up our minds).
But if we take the ego merely as a practical unity, composed for purposes of provisional survey; in fact, take it as a more strongly coherent group of elements, which is less strongly connected with other groups of this kind; questions like these will not arise and research will have a free outlook.
In his philosophical notes Lichtenberg says: "We become conscious of certain ideas that are not dependent upon us; and there are other ideas that, at least as we think, are dependent upon us. Where is the border-line? We know only the existence of our sensations, percepts, and thoughts. We should say, It thinks, just as we say, It lightens. It is going too far to say cogito, when we translate it by I think. Assuming the I, postulating it, is merely practical necessity." Though the method by which Lichtenberg arrives at this result is somewhat different from our own, we must nevertheless give our assent to the conclusion itself.