y 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 a