The Science of Breath, like many other teachings, has its esoteric or inner phase, as well as its exoteric or external. The physiological phase may be termed the outer or exoteric side of the subject, and the phase which we will now consider may be termed its esoteric or inner side. Occultists, in all ages and lands, have always taught, usually secretly to a few followers, that there was to be found in the air a substance or principle from which all activity, vitality and life was derived. They differed in their terms and names for this force, as well as in the details of the theory, but the main principle is to be found in all occult teachings and philosophies, and has for centuries formed a portion of the teachings of the Oriental Yogis.

In order to avoid misconceptions arising from the various theories regarding this great principle, which theories are usually attached to some name given the principle, we, in this work, will speak of the principle as "Prang," this word being the Sanscrit term meaning "Absolute Energy." Many occult authorities teach that the principle which the Hindus term "Prang" is the universal principle of energy or force, and that all energy or force is derived from that principle, or, rather, is a particular form of manifestation of that principle. These theories do not concern us in the consideration of the subject matter of this work, and we will therefore confine ourselves to an understanding of prana, as the principle of energy exhibited in all living things, which distinguishes them from a lifeless thing. We may consider it as the active principle of life-Vital Force, if you please. It is found in all forms of life, from the amoeba to man - from the most elementary form of plant life to the highest form of animal life.

Prana is all pervading. It is found in all things having life, and as the occult philosophy teaches that life is in all things - in every atom - the apparent lifelessness of some things being only a lesser degree of manifestation, we may understand their teachings that prana is everywhere, in everything. Prana must not be confounded with the Ego - that bit of Divine Spirit in every soul, around which clusters matter and energy. Prana is merely a form of energy used by the Ego in its material manifestation. When the Ego leaves the body, the prana, being no longer under its control, responds only to the orders of the individual atoms, or groups of atoms, forming the body, and as the body disintegrates and is resolved to its original elements each atom takes with it sufficient prana to enable it to form new combinations, the unused prana returning to the great universal storehouse from which it came.

With the Ego in control, cohesion exists and the atoms are held together by the Will of the Ego.

Prana is the name by which we designate a universal principle, which principle is the essence of all motion, force or energy, whether manifested in gravitation, electricity, the revolution of the planets, and all forms of life, from the highest to the lowest. It may be called the soul of Force and Energy in all their forms, and that principle which, operating in a certain way, causes that form of activity which accompanies Life.

This great principle is in all forms of matter, and yet it is not matter. It is in the air, but it is not the air nor one of its chemical constituents. Animal and plant life breathe it in with the air, and yet if the air contained it not they would die even though they might be filled with air. It is taken up by the system along with the oxygen, and yet is not the oxygen. The Hebrew writer of the book of Genesis knew the difference between the atmospheric air and the mysterious and potent principle contained within it. He speaks of neshemet ruach chayim, which, translated, means "the breath of the spirit of life." In the Hebrew neshemet means the ordinary breath of atmospheric air, and chayim means life or lives, while the word ruach means the "spirit of life," which occultists claim is the same principle which we speak of as prana. Prana is in the atmospheric air, but it is also elsewhere, and it penetrates where the air cannot reach. The oxygen in the air plays an important part in sustaining animal life, and the carbon plays a similar part with plant life, but prana has its own distinct part to play in the manifestation of life, aside from the physiological functions.

We are constantly inhaling the air charged with prana. and are as constantly extracting the latter from the air and appropriating it to our uses. Prana is found in its freest state in the atmospheric air, which when fresh is fairly charged with it, and we draw it to us more easily from the air than from any other source. In ordinary breathing we absorb and extract a normal supply of prana, but by controlled and regulated breathing (generally known as Yogi breathing) we are enabled to extract a greater supply, which is stored away in the brain and nerve centres, to be used when necessary. We may store away prana, just as the storage battery stores away electricity.

The many powers attributed to advanced occultists is due largely to their knowledge of this fact and their intelligent use of this stored-up energy. The Yogis know that by certain forms of breathing they establish certain relations with the supply of prana and may draw on the same for what they require. Not only do they strengthen all parts of their body in this way, but the brain itself may receive increased energy from the same source, and latent faculties be developed and psychic powers attained. One who has mastered the science of storing away prana, either consciously or unconsciously, often radiates vitality and strength which is felt by those coming in contact with him, and such a person may impart this strength to others, and give them increased vitality and health. What is called "magnetic healing" is performed in this way, although many practitioners are not aware of the source of their power. Western scientists have been dimly aware of this great principle with which the air is charged, but finding that they could find no chemical trace of it, or make it register on any of their instruments, they have generally treated the Oriental theory with disdain. They could not explain this principle, and so denied it. They seem, however, to recognize that the air in certain places possesses a greater amount of "something "and sick people are directed by their physicians to seek such places in hopes of regaining lost health.

The oxygen in the air is appropriated by the blood and is made use of by the circulatory system. The prana in the air is appropriated by the nervous system, and is used in its work. And as the oxygenated blood is carried to all parts of the system, building up and replenishing, so is the prana carried to all parts of the nervous system, adding strength and vitality. If we think of prana as being the active principle of what we call "vitality," we will be able to form a much clearer idea of what an important part it plays in our lives. Just as is the oxygen in the, blood used up by the wants of the system, so the supply of prana taken up by the nervous system is exhausted by our thinking, willing, acting, etc., and in consequence constant replenishing is necessary. Every thought, every act, every effort of the will, every motion of a muscle, uses up a certain amount of what we call nerve force, which is really a form of prana. To move a muscle the brain sends out an impulse over the nerves, and the muscle contracts, and so much prana is expended. When it is remembered that the greater portion of prana acquired by man comes to him from the air inhaled, the importance of proper breathing is readily understood.