or 'to blow', refers to the motive power of prāṇa). As the daemons of Plato's occultism are said to control the operations of the Cosmic Body, so these vāyu, composed of negative prāṇa, control the operations of the human body. Five are fundamental: (1) the prāṇa, controlling inspiration; (2) the udāna, controlling the ascending vital-force (or vital-air); (3) the apāna, controlling the downward vital-force, which expels wind, excrement, urine, and semen; (4) the samāna, as the collective force of the vāyu, kindles the fire of the body whereby food is digested and then distributed by the blood; and (5) the vyāna, controlling division and diffusion in all metabolic processes. The five minor airs are the Nāga, kūrmma, kṛịkara, deva-datta, and dhananjaya, which produce, respectively, hiccuping, opening and closing of the eyes, assistance to digestion, yawning, and distension.
The Psychic Nerves or Channels (Skt. Nāḍī).—There are next mentioned in our text the Psychic Nerves. Sanskrit works on Yoga say that there are fourteen principal nāḍī and hundreds of thousands of minor nāḍī in the human body, just as Western physiologists say that there are so many chief nerves and minor nerves. But the nāḍī of the East and the nerves of the West, although literally the same in name, are not synonymous. The nāḍī are invisible channels for the flow of psychic forces whose conducting agents are the vital-airs (vāyu).
Of the fourteen principal nāḍī, there are three which are of fundamental importance. These are, to follow our text, the median-nerve (Skt. suṣḥumnā-nāḍī), the left nerve (īḍā-nāḍī), and the right nerve (pingalā-nāḍī). The suṣḥumnā-nāḍī is the chief or median-nerve, situated in the hollow of the spinal column (Skt. Brāhma-daṇḍa), the Mt. Meru of the human body, man being regarded as the microcosm of the macrocosm. The īḍā-nāḍī, to the left, and the pingalā-nāḍī, to the right, coil round it as the two serpents coil round the caduceus carried by the messenger-god Hermes. It is believed that this ancient herald's wand symbolizes the suṣḥumnā-nāḍī, and the twining serpents the īḍā-nāḍī and the pingalā-nāḍī. If so, we see again how the esoteric symbol-code of the West corresponds to that of the East.
