earth for human
beings thereon to appear as minute moving things, in the semblance,
let us say, of insects infesting an apple. It is clear that from
this point of view these beings have a freedom of movement in their
"space" (the surface of the earth), of which the larger unit is not
possessed; for while the earth itself can follow only a _line_, its
inhabitants are free to move in the two dimensions of the surface of
the earth.

Abandoning our last coign of vantage, let us descend in imagination
and mingle familiarly among men. We now perceive that these
creatures which from a distance appeared as though flat upon the
earth's surface, are in reality erect at right angles to its plane,
and that they are endowed with the power to move their members in
_three dimensions_. Indeed, man's ability to traverse the surface
of the earth is wholly dependent upon his power of three-dimensional
movement. Observe that with each transfer of our attention from
greater units to smaller, we appear to be dealing with a power of
movement in an additional dimension.

Looking now in thought not _at_ the body of man, but _within_ it, we
apprehend an ordered universe immensely vast in proportion to that
physical ultimate we name the electron, as is the firmament immensely
vast in proportion to a single star. It has been suggested that in
the infinitely minute of organic bodies there is a power of movement
in a _fourth_ dimension. If so, such four-dimensional movement may
be the proximate cause of the phenomenon of _growth_--of those
chemical changes and renewals whereby an organism is enabled to
expand in three-dimensional space, just as by a three-dimensional
power of movement (the act of walking) man is able to traverse his
two-dimensional space--the surface of the earth.

--AND BEYOND

Proceed still further. Behind such organic change--assumed to be
four-dimensional--there is the determination of some _will-to-live_,
which manifests itself to consciousness as thought and as desire.
Into these the idea of space does not enter: we think of them as in
_time_. But if there are developments of other dimensions of space,
thought and emotion may themselves be discovered to have space
relations; that is, they may find expression in the forms of _higher_
spaces. Thus is opened up one of those rich vistas in which the
subject of the fourth dimension abounds, but into which we
can only glance in passing. If there are such higher-dimensional