consequently the material correspondence is Motion, as distinguished from
the simple diffused ether which is the correspondence of mere awareness of
Being, But what sort of motion? Is the material movement evolved at this
stage bound to take any particular form? A little consideration will show
us that it is. At this initial stage, the first awakening, so to say, of
Spirit into activity, its consciousness can only be that of activity
_absolute_; that is, not as related to any other mode of activity because
as yet there is none, but only as related to an all-embracing Being; so
that the only possible conception of Activity at this stage is that of
_Self-sustained_ activity, not depending on any preceding mode of activity
because there is none. The law of reciprocity therefore demands a similar
self-sustained motion in the material correspondence, and mathematical
considerations show that the only sort of motion which can sustain a
self-supporting body moving _in vacuo_ is a rotary motion bringing the body
itself into a spherical form. Now this is exactly what we find at both
extremes of the material world. At the big end the spheres of the planets
rotating on their axes and revolving round the sun; and at the little end
the spheres of the atoms consisting of particles which, modern science
tells us, in like manner rotate round a common center at distances which
are astronomical as compared with their own mass. Thus the two ultimate
units of physical manifestation, the atom and the planet, both follow the
same law of self-sustained motion which we have found that, on _a priori_
grounds, they ought in order to express the primary activity of Spirit. And
we may note in passing that this rotary, or _absolute_, motion is the
combination of the only two possible _relative_ modes of motion, namely,
motion from a point and motion to it, that is to say centrifugal and
centripetal motion; so that in rotary, or absolute, motion we find that
both the polarities of motion are included, thus repeating on the purely
mechanical side the primordial principle of the Unity including the Duality
in itself.