Before the reader makes up his mind to do this, I beg him to consider the following:-- (1) If the only external world of which we have a right to speak at all is a construct in the mind or _ego_, we may certainly affirm that the world is in the _ego_, but does it sound sensible to say that the _ego_ is somewhere in the world? (2) If all external things are really inside the mind, and are only "projected" outwards, of course our own bodies, sense-organs, nerves, and brains, are really inside and are merely projected outwards. Now, do the sense-impressions of which everything is to be constructed "come flowing in" along these nerves that are really inside? (3) Can we say, when a nerve lies entirely within the mind or _ego_, that this same mind or _ego_ is nearer to one end of the nerve than it is to the other? How shall we picture to ourselves "the conscious _ego_ of each one of us seated at the brain terminals of the sensory nerves"? How can the _ego_ place the whole of itself at the end of a nerve which it has constructed within itself? And why is it more difficult for it to get to one end of a nerve like this than it is to get to the other? (4) Why should the thing "at the other end of the nerve" remain unknown and unknowable? Since the nerve is entirely in the mind, is purely a mental construct, can anything whatever be at the end of it without being in the mind? And if the thing in question is not in the mind, how are we going to prove that it is any nearer to one end of a nerve which is inside the mind than it is to the other? If it may really be said to be at the end of the nerve, why may we not know it quite as well as we do the end of the nerve, or any other mental construct? It must be clear to the careful reader of Professor Pearson's paragraphs, that he does not confine himself strictly to the world of mere "projections," to an outer world which is really _inner_. If he did this, the distinction between inner and outer would disappear. Let us consider for a moment the imprisoned clerk. He is in a telephone exchange, about him are wires and subscribers. He gets only sounds and must build up his whole universe of things out of sounds. Now we are supposing him to be in a telephone exchange, to be receiving messages, to be building up a world out of these messages. Do we for a moment think of him as building up, out of the messages which came along the wires, those identical wires which carried the messages and the subscribers which sent them? Never! we distinguish between the exchange, with its wires and subscribers, and the messages received and worked up into a world. In picturing to ourselves the telephone exchange, we are doing what the plain man and the psychologist do when they distinguish between mind and body,--they never suppose that the messages which come through the senses are identical with the senses through which they come.