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.
But the Spirit wants something more than mechanical motion, something more alive than the preliminary Rota, and so the first step toward individualized consciousness meets us in plant life.

Then on the principle that each successive stage affords the platform for a further outlook, plant life is followed by animal life, and this by the Human order in which the liberty of selecting its own conditions is immensely extended.

In this way the Spirit's expression of itself has now reached the point where its polar complementary, or Reciprocal, manifests as Intellectual Man--thus constituting the Fourth great stage of Spirit's Self-recognition.