Now the assertion that these actions are the causes of the attainment of salvation brings up the question of the exact natures of their operation with regard to this supreme attainment. Bhāshyakara says with respect to this that they are the causes of the separation of the impurities of the mind just as an axe is the cause of the splitting of a piece of wood; and again they are the causes of the attainment of the supreme knowledge just as dhaṛma is the cause of happiness. It must be remembered that according to the Yoga theory causation is viewed as mere transformation of energy; the operation of concomitant causes only removes obstacles impeding the progress of these transformations in a particular direction; no cause can of itself produce any effect, and the only way in which it can help the production of an effect into which the causal state passes out of its own immanent energy by the principles of conservation and transformation of energy, is by removing the intervening obstacles. Thus just as the passage of citta into a happy state is helped by dharma removing the intervening obstacles, so also the passage of the citta into the state of attainment of true knowledge is helped by the removal of obstructions due to the performance of the yogāṅgas; the necessary obstructions being removed, the citta passes naturally of itself into this infinite state of attainment of true knowledge, in which all finitude is merged.
In connection with this, Vyāsa mentions nine kinds of operation of causes: (1) cause of birth; (2) of preservation; (3) of manifestation; (4) of modification; (5) knowledge of a premise leading to a deduction; (6) of otherness; (7) of separation; (8) of attainment; (9) of upholding (Vyāsabhāshya, II. 28.)
The principle of conservation of energy and transformation of energy being the root idea of causation in this system, these different aspects represent the different points of view in which the word causation is generally used.
Thus, the first aspect as the cause of birth or production is seen when knowledge springs from manas which renders indefinite cognition definite so that mind is called the cause of the birth of knowledge. Here mind is the material cause (upādāna kāraṇa) of the production of knowledge, for knowledge is nothing but manas with its particular modifications as states (Yoga-vārttika, II. 18). The difference of these positive cause from āptikāraṇa, which operates only in a negative way and helps production, in an indirect way by the removal of obstacles, is quite manifest. The sthitikāraṇa or cause through which things are preserved as they are, is the end they serve; thus the serviceability of purusha is the cause of the existence and preservation of the mind as it is, and not only of mind but of all our phenomenal experiences.
The third cause of the abhivyaktikāraṇa or manifestation which is compared to a lamp which manifests things before our view is an epistemological cause, and as such includes all sense activity in connection with material objects which produce cognition.
Then come the fourth and the fifth causes, vikāra (change) and pratyaya (inseparable connection); thus the cause of change (vikāra) is exemplified as that which causes a change; thus the manas suffers a change by the objects presented to it, just as bile changes and digests the food that is eaten; the cause of pratyaya[[41]] is that in which from inseparable connection, with the knowledge of the premise (e.g. there is smoke in the hill) we can also have inferential knowledge of the other (e.g. there is fire in the hill). The sixth cause as otherness (anyatva) is that which effects changes of form as that brought about by a goldsmith in gold when he makes a bangle from it, and then again a necklace, is regarded as differing from the change spoken of as vikāra. Now the difference between the gold being turned into bangles or necklaces and the raw rice being turned into soft rice is this, that in the former case when bangles are made out of gold, the gold remains the same in each case, whereas in the case of the production of cooked rice from raw by fire, the case is different, for heat changes paddy in a far more definite way; goldsmith and heat are both indeed efficient causes, but the former only effects mechanical changes of shape and form, whereas the latter is the cause of structural and chemical changes. Of course these are only examples from the physical world, their causal operations in the mental sphere varying in a corresponding manner; thus the change produced in the mind by the presentation of different objects, follows a law which is the same as is found in the physical world, when the same object causes different kinds of feelings in different persons; when ignorance causes forgetfulness in a thing, anger makes it painful and desire makes it pleasurable, but knowledge of its true reality produces indifference; there is thus the same kind of causal change as is found in the external world. Next for consideration is the cause of separation (viyoga) which is only a negative aspect of the positive side of the causes of transformations, as in the gradual extinction of impurities, consequent upon the transformation of the citta towards the attainment of the supreme state of absolute independence through discriminative knowledge. The last cause for consideration is that of upholding (dhṛti); thus the body upholds the senses and supports them for the actualisation of their activities in the body, just as the five gross elements are the upholding causes of organic bodies; the bodies of animals, men, etc., also employ one another for mutual support. Thus the human body lives by eating the bodies of many animals; the bodies of tigers, etc., live on the bodies of men and other animals; many animals live on the bodies of plants, etc. (Tattvavaiśāradī, II. 28). The four kinds of causes mentioned in Śaṅkara’s works and grammatical commentaries like that of Susheṇa, viz.: utpādya, vikāryya, āpya and saṃskāryya, are all included within the nine causes contained mentioned by Vyāsa.
The yogāṅgas not only remove the impurities of the mind but help it further by removing obstacles in the way of attaining the highest perfection of discriminative knowledge. Thus they are the causes in a double sense (1) of the dissociation of impurities (viyogakāraṇa); (2) of removing obstacles which impede the course of the mind in attaining the highest development (āptikāraṇa).
Coming now to the yogāṅgas, we enumerate them thus:—restraint, observance, posture, regulation of breath, abstraction, concentration, meditation and trance: these are the eight accessories of Yoga.
It must be remembered that abhyāsa and vairāgya and also the five means of attaining Yoga, viz.: śraddhā, vīryya, etc., which are not different from abhyāsa and vairāgya, are by their very nature included within the yogāṅgas mentioned above, and are not to be considered as independent means different from them. The parikarmas or embellishments of the mind spoken of in the first chapter, with which we shall deal later on, are also included under the three yogāṅgas dhāraṇā, dhyāna and samādhi. The five means śraddhā, vīryya, smṛti, samādhi and prajñā are said to be included under asceticism (tapaḥ) studies (svādhyāya) and devotion to God of the niyamas and vairāgya in contentment.
In order to understand these better, we will first give the definitions of the yogāṅgas and then discuss them and ascertain their relative values for a man striving to attain the highest perfection of Yoga.