The second is described as the monadic, because in it exist those Sparks of the divine Life which we call the human Monads; but neither of these can be touched by the highest clairvoyant investigations at present possible for us.

The third sphere, whose atoms contain 2,401 bubbles, is called the spiritual world, because in it functions the highest Spirit in man as now constituted.

The fourth is the intuitional world, [Previously called in Theosophical literature the buddhic plane.] because from it come the highest intuitions.

The fifth is the mental world, because from its matter is built the mind of man.

The sixth is called the emotional or astral world, because the emotions of man cause undulations in its matter.