The “cell” is an illusion. It is merely a word. It has no existence as a material thing, for any cell is composed of other cells. What, then, is a cell? It is the ideal form within which the actual physical atoms—made up of the “lives”—arrange themselves. As it is admitted that the physical molecules are forever rushing away from the body, they must be leaving the cells each moment. Hence there is no physical cell, but the privative limits of one, the ideal walls and general shape. The molecules assume position within the ideal shape according to the laws of nature, and leave it again almost at once to give place to other atoms. And as it is thus with the body, so is it with the earth and with the solar system. Thus also is it, though in slower measure, with all material objects. They are all in constant motion and change. This is modern and also ancient wisdom. This is the physical explanation of clairvoyance, clairaudience, telepathy, and mind-reading. It helps to show us what a deluding and unsatisfactory thing our body is. Although, strictly speaking, the second constituent of man is the Astral Body—called in Sanscrit _Linga Sarira_—we will consider Life Energy—or _Prana_ and _Jiva_ in Sanscrit—together, because to our observation the phenomenon of life is more plainly exhibited in connection with the body. Life is not the result of the operation of the organs, nor is it gone when the body dissolves. It is a universally pervasive principle. It is the ocean in which the earth floats; it permeates the globe and every being and object on it. It works unceasingly on and around us, pulsating against and through us forever. When we occupy a body we merely use a more specialized instrument than any other for dealing with both _Prana_ and _Jiva_. Strictly speaking, _Prana_ is breath; and as breath is necessary for continuance of life in the human machine, that is the better word. _Jiva_ means “life”, and also is applied to the living soul, for the life in general is derived from the Supreme Life itself. _Jiva_ is therefore capable of general application, whereas _Prana_ is more particular. It cannot be said that one has a definite amount of this Life Energy which will fly back to its source should the body be burned, but rather that it works with whatever be the mass of matter in it. We, as it were, secrete or use it as we live. For whether we are alive or dead, life-energy is still there; in life among our organs sustaining them, in death among the innumerable creatures that arise from our destruction. We can no more do away with this life than we can erase the air in which the bird floats, and like the air it fills all the spaces on the planet, so that nowhere can we lose the benefit of it nor escape its final crushing power. But in working upon the physical body this life—_Prana_—needs a vehicle, means, or guide, and this vehicle is the astral body.