The bases of this Yoga are of a highly metaphysical and scientific character. For its understanding there is required a full acquaintance with Indian philosophy, religious doctrine, and ritual in general, and in particular with that presentment of these three matters which is given in the Sakta and Monistic (Advaita) Saiva-Tantras. It would need more than a bulky volume to describe and explain in any detail the nature and meaning of this Yoga, and the bases on which it rests. I must, therefore, assume in the reader either this general knowledge or a desire to acquire it, and confine myself to such an exposition of general principles and leading facts as will supply the key by which the doors leading to a theoretical knowledge of the subject may be opened by those desirous of passing through and beyond them, and as will thus facilitate the understanding of the difficult texts here translated.
For on the practical side I can merely reproduce the directions given in the books together with such explanations of them as I have received orally. Those who wish to go farther, and to put into actual process this Yoga, must first satisfy themselves of the value and suitability of this Yoga and the learn directly of a Guru who has himself been through it (Siddha). His experience alone will say whether the aspirant is capable of success.
The ultimate or irreducible reality is 'Spirit' in the sense of pure consciousness (Cit, Samvit) from out of which as and by its Power (Sakti), Mind and Matter proceed. Spirit is one. There are no degrees or differences in Spirit. The Spirit which is in man is the one Spirit which is in everything and which, as the object of worship, is the Lord (Isvara) or God. Mind and Matter are many and of many degrees and qualities. Atma or Spirit as such is the Whole (Purna) without section (Akhanda). Mind and Matter are parts in that Whole. They are not-whole (Apurna) and are the section (Khanda). Spirit is infinite (Aparicchinna) and formless (Arupa). Mind and Matter are finite (Paricchinna) and with form (Rupa). Atma is unchanged and inactive. Its power (sakti) is active and changes in the form of Mind and Matter. Pure consciousness is Cit or Samvit (Brahman, Satchidananda). Matter as such is the unconscious. And Mind too is unconscious according to Vedanta. For all that is not the conscious self, is the unconscious object: This does not mean that is unconscious of itself. On the contrary all is essentially consciousness, but that it is unconscious because it is the object of the conscious self. For mind limits Consciousness so as to enable man to have finite experience. There is no Mind without consciousness as its background, though supreme Consciousness is Mindless (Amanah). Where there is no mind (Amanah), there is no limitation. Consciousness remaining in one aspect unchanged changes in its other aspect as active power which manifests as Mind and Body. Man then is Pure Consciousness (Cit) vehicled by it Power as Mind and Body.
In Theology, this pure consciousness is Siva, and His Power (Sakti) who as She is in Her formless self is one with Him. She is the great Devi, the mother of the universe who as the Life-Force resides in man's body in its lowest centre at the base of the spine just as Siva is realized in the highest centre, the cerebrum or Sahasrara Padma. Completed Yoga is the Union of Her and Him in the body of the Sadhaka. This is Laya or dissolution, the revers of Srsti or involution of Spirit in Mind and Matter.
Some worship predominantly the masculine or right side of the conjoint male and female figure (Ardhanarisvara). Some, the saktas, predominantly worship the left, and call Her Mother, for She is the Great Mother (Magna Mater), the Mahadevi who conceives, bears, and nourishes the universe sprung from Her womb (Yoni). This is so because She is the active aspect of consciousness, imagining (Srsti-kalpana) the world to be, according to the impressions (samskara) derived from enjoyment and suffering in former worlds. It is held natural to worship Her as Mother. The first Mantra into which all men are initiated is the word Ma (Mother). It is their first word and generally their last. The father is a mere helper (Sahakari-matra) of the Mother. The whole world of the five elements also springs from the Active Consciousness or Sakti, and is Her manfestation (purna-vikasa). Therefore, men worship the Mother, than whom is none more tender, saluting Her smiling beauty as the rosy Tripurasundari, the source of the universe, and Her awe-inspiring grandeur as Kali, who takes it back into Herself. Here we are concerned with Yoga which is the realisation of the union of the Mother and Lord aspects in that state of consciousness which is the Absolute.