This article is classified "Fictional"
Although it may seem quite improbable, it may just be possible that, if only
once in a lifetime, you'll be confronted with a creature from the fourth
dimension. With a creature from the fourth dimension I don't mean a
creature that can move freely in time or such [1], but a creature that
normally lives in a universe with four spatial dimensions instead of three,
all at right angles to each other. When you meet this creature you may at
first not be aware that it *is* a creature from the fourth dimension. You
may only be aware that you are witnessing things that are absolutely not
normal and that cannot be explained by the physics we know today. In this
article I will try and scetch how you can recognize that you are dealing
with such a creature, what its appearence is and what advantages it has over
us.
For this purpose you should first have an idea of what we would look like in
a two dimensional world. I'm sure most people have at one time or other
read some things about two dimensional worlds [2], so I won't go into that
(How convenient for me). We extrapolate these ideas to a higher dimension
[3]. We look at our advantages over two dimensional beings and easily find
out what advantages the four dimensional creatures have over us.
Suddenly it appears in front of you, a three dimensional shape that changes
appearance and size fast. When you try to communicate with it by talking,
it constantly changes shape because it has to alternate between putting its
ears and mouth in our dimension, just like we would turn our head sideways
to hear from and talk in a planar universe. It would have one arm on the
outside and one on what *we* call the inside. What its inside would be like
is impossible to understand for us. It would have some 13 fingers,
tentacle-like, that in our dimension would look like a hand with an
alternating number of fingers. This argument made sense to me once, but I
have quite forgotten why.
It would be able to look at our insides and inside everything else, just
like we can view a picture of, say, a cut of a cat's brain. If it would be
able to talk in right angles to our three dimensions, its sound would seem
to come from all around us.
I could go on and on with this list, but it is my experience that it gets
boring after a while. At least you've now got some clues to know the
explanation to certain phenomena you might or might not once encounter.
Now someone else try to speculate what it would be to meet a creature from
a universe with three spatial dimensions, just like us, but with two
temporal dimensions at right angles to each other.
[1] Kurt Vonnegut, Slaughterhouse 5
[2] I have, in A.K. Dewdney's The Planiverse, but I got bored halfway.
A famous other book is E.T. Abbot's Flatland
[3] See Rudy Rucker's The Fourth Dimension, which I unfortunately haven't
read.