live. It is equally obvious that a strictly religious man occupies a different world than that of a materialist. The fortunate man lives in a happy world; the unfortunate man sees a world of misery. One man is happy with little, another is miserable with much. Each sees the world from his own point of view, which is the same as saying that each lives in his own world. Therefore there are as many worlds as there are points of view."

"But," I objected, "that theory is to disregard reality. Out of all the different points of view, there must be one that is right, and all the rest are wrong."

"One would think so," agreed the professor. "One would think that between the point of view of you, for instance, as contrasted with that of, say van Manderpootz, there would be small doubt as to which was correct. However, early in the twentieth century, Heisenberg enunciated his Principle of Uncertainty, which proved beyond argument that a completely accurate scientific picture of the world is quite impossible, that the law of cause and effect is merely a phase of the law of chance, that no infallible predictions can ever be made, and that what science used to call natural laws are really only descriptions of the way in which the human mind perceives nature. In other words, the character of the world depends entirely on the mind observing it, or, to return to my earlier statement, the point of view."

"But no one can ever really understand another person's point of view," I said. "It isn't fair to undermine the whole basis of science because you can't be sure that the color we both call red wouldn't look green to you if you could see it through my eyes."

"Ah!" said van Manderpootz triumphantly. "So we come now to my attitudinizor. Suppose that it were possible for me to see through your eyes, or you through mine. Do you see what a boon such an ability would be to humanity? Not only from the standpoint of science, but also because it would obviate all troubles due to misunderstandings. And even more." Shaking his finger, the professor recited oracularly, "'Oh, wad some pow'r the giftie gie us to see oursel's as ithers see us.' Van Manderpootz is that power, Dixon. Through my attitudinizor, one may at last adopt the viewpoint of another. The poet's plaint of more than two centuries ago is answered at last."

"How the devil do you see through somebody else's eyes?"

"Very simply. You will recall the idealizator. Now it is obvious that when I peered over your shoulder and perceived in the mirror your conception of the ideal woman, I was, to a certain extent, adopting your point of view. In that case the psychons given off by your mind were converted into quanta of visible light, which could be seen. In the case of my attitudinizor, the process is exactly reversed. One flashes the beam of this light on the subject whose point of view is desired; the visible light is reflected back with a certain accompaniment of psychons, which are here intensified to a degree which will permit them to be, so to speak, appreciated?"

"Psychons?"

"Have you already forgotten my discovery of the unit particle of thought? Must I explain again how the cosmons, chronons, spations, psychons, and all other particles are interchangeable? And that," he continued abstractedly, "leads to certain interesting speculations. Suppose I were to convert, say, a ton of material protons and electrons into spations—that is, convert matter into space. I calculate that a ton of matter will produce approximately a cubic mile of space. Now the question is, where would we put it, since all the space we have is already occupied by space? Or if I manufactured an hour or two of time? It is obvious that we have no time to fit in an extra couple of hours, since all our time is already accounted for. Doubtless it will take a certain amount of thought for even van Manderpootz to solve these problems, but at the moment I am curious to watch the workings of the attitudinizor. Suppose you put it on, Dixon."

"I? Haven't you