Prakṛti, though a substantive entity is yet a potential power, being actualised as its various modifications, the aviśeshas and the viśeshas. Being of the nature of power, the movement by which it actualises itself is immanent within itself and not caused from without. The operation of the concomitant conditions is only manifested in the removal of the negative barriers by which the power was stopped or prevented from actualising itself. Being of the nature of power, its potentiality means that it is kept in equilibrium by virtue of the opposing tendencies inherent within it, which serve to obstruct one another and are therefore called the āvaraṇa śakti. Of course it is evident that there is no real or absolute distinction between the opposing force (āvaraṇa śakti) and the energising force (kāryyakarī śakti); they may be called so only relatively, for the same tendency which may appear as the āvaraṇa śakti of some tendencies may appear as the kāryyakarī śakti elsewhere. The example chosen to explain the nature of prakṛti and its modifications conceived as power tending towards actuality from potentiality in the Vyāsa-bhāshya is that of a sheet of water enclosed by temporary walls within a field, but always tending to run out of it. As soon as the temporary wall is broken in some direction, the water rushes out of itself, and what one has to do is to break the wall at a particular place. Prakṛti is also the potential for all the infinite diversity of things in the phenomenal world, but the potential tendency of all these mutually opposed and diverse things cannot be actualised together. Owing to the concomitant conditions when the barrier of a certain tendency is removed, it at once actualises itself in its effect and so on.

We can only expect to get any effect from any cause if the necessary barriers can be removed, for everything is everything potentially and it is only necessary to remove the particular barrier which is obstructing the power from actualising itself in that particular effect towards which it is always potentially tending. Thus Nandī who was a man is at once turned into a god for his particular merit, which served to break all the barriers of the potential tendency of his body towards becoming divine, so that the barriers being removed the potential power of the prakṛti of his body at once actualises itself in the divine body.

The Vyāsa-bhāshya (III. 14) mentions four sorts of concomitant conditions which can serve to break the barrier in a particular way and thus determine the mode or form of the actualisations of the potential. These are (1) ākāra, form and constitution of a thing; deśa, place, (3) kāla, time; thus from a piece of stone, the shoot of a plant cannot proceed, for the arrangement of the particles in stone is such that it will oppose and stand as a bar to its potential tendencies to develop into the shoot of a plant; of course if these barriers could be removed, say by the will of God, as Vijñāna Bhikshu says, then it is not impossible that the shoot of a plant might grow from a stone. By the will of God poison may be turned into nectar and nectar into poison, and there is no absolute certainty of the course of the evolutionary process, for God’s will can make any change in the direction of its process (avyavasthitākhilapariṇāmo bhavatyeva, III. 14).

According to the Sāṃkhya-Pātañjala theory dharma, merit, can only be said to accrue from those actions which lead to a man’s salvation, and adharma from just the opposite course of conduct. When it is said that these can remove the barriers of the prakṛti and thus determine its modifications, it amounts almost to saying that the modifications of the prakṛti are being regulated by the moral conditions of man. According to the different stages of man’s moral evolution, different kinds of merit, dharma or adharma, accrue, and these again regulate the various physical and mental phenomena according to which a man may be affected either pleasurably or painfully. It must, however, be always remembered that the dharma and adharma are also the productions of prakṛti, and as such cannot affect it except by behaving as the cause for the removal of the opposite obstructions—the dharma for removing the obstructions of adharma and adharma for those of dharma. Vijñāna Bhikshu and Nāgeśa agree here in saying that the modifications due to dharma and adharma are those which affect the bodies and senses. What they mean is possibly this, that it is dharma or adharma alone which guides the transformations of the bodies and senses of all living beings in general and the Yogins.

The body of a person and his senses are continually decaying and being reconstructed by refilling from the gross elements and from ahaṃkāra respectively. These refillings proceed automatically and naturally; but they follow the teleological purpose as chalked out by the law of karma in accordance with the virtues or vices of a man. Thus the gross insult to which the sages were subjected by Nahusha[[36]] was so effective a sin that by its influence the refilling of Nahusha’s body and the senses was stopped and the body and senses of a snake were directly produced by a process of refilling from the gross elements and ahaṃkāra, for providing him with a body in which he could undergo the sufferings which were his due owing to the enormity of his vice. Thus by his vicious action the whole machinery of prakṛti was set in operation so that he at once died and was immediately reborn as a snake. In another place Vācaspati “the virtuous enjoys happiness” as an illustration of the cause of dharma and adharma as controlling the course of the development of prakṛti. We therefore see that the sphere of merit and demerit lies in the helping of the formation of the particular bodies and senses (from the gross elements and ahaṃkāra respectively) suited to all living beings according to their stages of evolution and their growth, decay, or other sorts of their modifications as pleasure, pain, and also as illness or health. Thus it is by his particular merit that the Yogin can get his special body or men or animals can get their new bodies after leaving the old ones at death. Thus Yoga-vārttika says: “Merit by removing the obstructions of demerit causes the development of the body and the senses.”

As for Īśvara I do not remember that the Bhāshya or the sūtras ever mention Him as having anything to do with the controlling of the modifications of the prakṛti by removing the barriers, but all the later commentators agree in holding him responsible for the removal of all barriers in the way of prakṛtis development. So that Īśvara is the root cause of all the removal of barriers, including those that are affected by merit and demerit. Thus Vācaspati says (IV. 3): Īśvarasyāpi dharmādhishṭhānārthaṃ pratibandhāpanaya eva vyāpāro, i.e. God stands as the cause of the removal of such obstacles in the prakṛti as may lead to the fruition of merit or demerit.

Yoga-vārttika and Nāgeśa agree in holding Īśvara responsible for the removal of all obstacles in the way of the evolution of prakṛti. Thus Bhikshu says that God rouses prakṛti by breaking the opposing forces of the state of equilibrium and also of the course of evolution (IV. 3).

It is on account of God that we can do good or bad actions and thus acquire merit or demerit. Of course God is not active and cannot cause any motion in prakṛti. But He by His very presence causes the obstacles, as the barriers in the way of prakṛti’s development, to be removed, in such a way that He stands ultimately responsible for the removal of all obstacles in the way of prakṛti’s development and thus also of all obstacles in the way of men’s performance of good or bad deeds. Man’s good or bad deeds “puṇyakarma,” apuṇyakarma, dharma or adharma serve to remove the obstacles of prakṛti in such a way as to result in pleasurable or painful effects; but it is by God’s help that the barriers of prakṛti are removed and it yields itself in such a way that a man may perform good or bad deeds according to his desire. Nīlakaṇṭha, however, by his quotations in explanation of 300/2, Śāntiparva, leads us to suppose that he regards God’s will as wholly responsible for the performance of our good or bad actions. For if we lay stress on his quotation “He makes him do good deeds whom He wants to raise, and He makes him commit bad deeds whom He wants to throw down,” it appears that he whom God wants to raise is made to perform good actions and he whom God wants to throw downwards is made to commit bad actions. But this seems to be a very bold idea, as it will altogether nullify the least vestige of freedom in and responsibility for our actions and is unsupported by the evidence of other commentators. Vijñāna Bhikshu also says with reference to this śruti in his Vijñānamṛta-bhāshya, III. 33: “As there is an infinite regressus between the causal connection of seed and shoot, so one karma is being determined by the previous karma and so on; there is no beginning to this chain.” So we take the superintendence of merits and demerits (dharmādhispṭhānatā) by Īśvara to mean only in a general way the help that is offered by Him in removing the obstructions of the external world in such a manner that it may be possible for a man to perform practically meritorious acts in the external world.

Nīlakaṇṭha commenting on the Yoga view says that “like a piece of magnet, God though inactive, may by His very presence stir up prakṛti and help His devotees. So the Yoga holds that for the granting of emancipation God has to be admitted” (Śāntiparva, 300/2).

In support of our view we also find that it is by God’s influence that the unalterable nature of the external world is held fast and a limit imposed on the powers of man in producing changes in the external world. Thus Vācaspati in explaining the Bhāshya (III. 45) says: “Though capable of doing it, yet he does not change the order of things, because another earlier omnipotent being had wished the things to be such as they were. They would not disobey the orders of the omnipotent God.”