Can a cube that does not last for any time at all, have a real
existence?
Filby became pensive. Clearly, the Time Traveller proceeded, any
real body must have extension in _four_ directions: it must have
Length, Breadth, Thickness, and Duration. But through a natural
infirmity of the flesh, which I will explain to you in a moment, we
incline to overlook this fact. There are really four dimensions, three
which we call the three planes of Space, and a fourth, Time. There is,
however, a tendency to draw an unreal distinction between the former
three dimensions and the latter, because it happens that our
consciousness moves intermittently in one direction along the latter
from the beginning to the end of our lives.
That, said a very young man, making spasmodic efforts to relight his
cigar over the lamp; that . . . very clear indeed.
Now, it is very remarkable that this is so extensively overlooked,
continued the Time Traveller, with a slight accession of cheerfulness.
Really this is what is meant by the Fourth Dimension, though some
people who talk about the Fourth Dimension do not know they mean it. It
is only another way of looking at Time. _There is no difference between
Time and any of the three dimensions of Space except that our
consciousness moves along it_. But some foolish people have got hold of
the wrong side of that idea. You have all heard what they have to say
about this Fourth Dimension?
_I_ have not, said the Provincial Mayor.
It is simply this. That Space, as our mathematicians have it, is
spoken of as having three dimensions, which one may call Length,
Breadth, and Thickness, and is always definable by reference to three
planes, each at right angles to the others. But some philosophical
people have been asking why _three_ dimensions particularly why not
another direction at right angles to the other three? and have even
tried to construct a Four-Dimensional geometry. Professor Simon Newcomb
was expounding this to the New York Mathematical Society only a month
or so ago. You know how on a flat surface, which has only two
dimensions, we can represent a figure of a three-dimensional solid, and
similarly they think that by models of three dimensions they could
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