Upon the destruction of impurities as a result of the practice of yoga, the lamp of knowledge arises. This culminates in discriminative discernment.

Bryant Commentary:

Patañjali here introduces the long-awaited aṇgas, limbs of yoga. It has by now been well established, says Vyāsa, that discriminative discernment, viveka, when achieved, is the cause of removing the conjunction between puruṣa and prakṛti, in other words, of removing ignorance such that liberation manifests. But what is the cause of achieving discriminative discernment? A means is required to achieve this. Milk may exist in the udders of the cow, says Vācaspati Miśra, but one needs a means or process to extract it. The means presented in this sūtra of attaining discriminative discernment is the practice of the eight limbs of yoga, yogā ṅgānuṣṭhāna, which will occupy the rest of the chapter.

By the practice of yoga, Patañjali states, impurity, aśuddhi, is destroyed, which, Vyāsa, reminds us, consists of the five kleśas, obstacles to yoga (ignorance, ego, attachment, aversion, and clinging to life). The notion of yoga destroying impurities goes back as far as the Āpastamba-dharma-sūtra of the fifth and fourth centuries B.C.E., which lists fifteen doṣas, faults, that are eliminated by its practice. When impurity is removed, the light of full knowledge, jñāna-dīpti, noted in this sūtra can shine forth, like the sun after the cold season, says Śaṅkara. Another way of putting this is that as the impurities of tamas and rajas dwindle, the luminosity and clarity inherent in sattva can manifest unimpeded. An impurity is something that intrudes on or contaminates another entity, in this case, rajas and tamas covering sattva (of course, sattva itself is ultimately a covering of puruṣa). The more the eightfold path is practiced, the more these impurities dwindle, and the more they dwindle, the more this light can correspondingly increase. This increase culminates in the desired discriminative discernment, a feature of pure sattva. Just as the axe slices wood from a tree, so the practice of these eight limbs slices the impurities away from the citta, says Vyāsa.

There is the widespread view that the continuity of the text comes to something of an abrupt end after II.27, with this sūtra typically deemed as initiating a new self-contained unit on the eight limbs. It is true that Patañjali does not make reference to the eight limbs prior to this point. Nor is there any explanation of the relationship among tapas, svādhyāya, and Īśvara-pranidhāna as the three ingredients of kriyā-yoga, and their occurrence as three of the five niyamas, the second limb, discussed below. And our modern notions of discursive continuity might have put the eight-limbed section in a separate pāda of its own, beginning with this sūtra.

But, again, one must be wary of submitting the cryptic sūtra style to modern notions of structural coherence. Just as the kriyā-yoga section introduced a new set of terms and conceptual analyses indispensable to explaining the mechanics (kleśas) underpinning the vṛttis such that the attainment of the goal of yoga might be better understood, so does this ensuing section dedicate itself to a necessarily more specific elaboration of the abhyāsa, practice, touched upon in I.12. As with the kriyā-yoga section, this increase of detail requires new terms and categories, but now pertaining to practice, articulated accordingly with less philosophical tone and content.

It is likely that Patañjali drew upon an existing tradition of eight-limbed yoga when composing his text (or modified the older tradition of six limbs), as well as a distinct tradition featuring kriyā-yoga. In other words, as a systematizer of existing traditions, Patañjali might well have merged two distinct but overlapping systems. This possibility is enhanced by the fact that the relationship between the three ingredients of kriyā-yoga and the identical three ingredients reappearing in the second limb of yoga, the niyamas, but now alongside two other ingredients, is not addressed by Patañjali.

Avidya Or Nescience As Its Cause.

The cause of conjunction is ignorance.

Bryant Commentary:

Vācaspati Miśra and Vijñānabhikṣu elaborate somewhat on the fourth possible cause of ignorance outlined in the previous sūtra. Creation in Hindu cosmology is cyclical. At the end of each cosmic cycle, all manifest reality, the world and the evolutes of prakṛti, dissolve back into their original source matrix along with the souls in saṁsāra—the puruṣas who have not attained liberation—and remain there latent and inactive until the next cosmic cycle begins anew. This primordial soup, called pradhāna, thus contains all the saṁskāras from all the cittas of all the individual puruṣas that had not had a chance to fructify during the last cycle.46 At the beginning of the new cycle, these saṁskāras reactivate and cause pradhāna to produce an individual citta for each puruṣa appropriate to the specific saṁskāras possessed by that same puruṣa at the end of the last cycle. The puruṣa is thus like a fish trapped in a net of its previous saṁskāras and karma, says Rāmānanda Sarasvatī. As a result of the puruṣa being reconnected with a citta, its previous saṁskāras, most notably the saṁskāra of ignorance (i.e., the misidentification between the puruṣa and prakṛti), reexert their influence. In other words, the puruṣa picks up where it left off. The point is, from this perspective, that it is the saṁskāras that cause ignorance. This cycle of creation and dissolution is eternal for the Yoga school until liberation occurs (saṁsāra has no beginning, but it has an ending). Since the eternality of this cycle is axiomatic, the Yoga school avoids having to account for any primordial saṁskāra of ignorance that may have activated the whole cycle in the first place.

When intelligence contains the saṁskāras of ignorance, says Vyāsa, it remains active in the realm of prakṛti and thus does not produce discrimination about the true nature of puruṣa. Saṁskāras impel the intelligence to perform the first of its two functions, as expressed in II.18, namely, to provide experience of prakṛti, and it is this that is the cause of bondage. Intelligence ceases its activity only when it has attained its alternative and ultimate function, which is to provide discrimination about the distinction between puruṣa and prakṛti. As was discussed in some detail in I.50, the saṁskāra of discrimination overpowers all other saṁskāras. When this happens, ignorance, avidyā, the cause, hetu, of bondage, is removed, and ignorance, we recall, is the support of the other kleśas, obstacles (II.3–4), so they, too, dissolve.
In other words, complete liberation occurs only when intelligence first provides discrimination and then ceases to act altogether. Although discrimination, a function of buddhi, is initially indispensable in attaining the goal of yoga, as long as it remains active, puruṣa is still connected with buddhi, and thus complete liberation is not realized. But discrimination eventually completely destroys ignorance and thus its own base, like fire destroys its own fuel, says Hariharānanda. This results in asamprajñāta-samādhi, the final goal of yoga.

One might argue, says Vyāsa, that this claim that full liberation occurs only after discrimination has dissolved itself is rather like an impotent man who, when asked by his wife why she does not have children as her sister has children, replies that he will beget children in her after he is dead. If intelligence cannot provide liberation while it is alive and active, why should one believe that it will do so after it becomes lifeless and inactive? Vyāsa affirms, again, that full and final liberation occurs precisely when the intelligence ceases to act. Intelligence ceases to act when ignorance is removed. And ignorance is removed by knowledge. In other words, bondage is caused by ignorance, ignorance is removed by knowledge, the discriminatory aspect of intelligence, and then intelligence, having performed its grand finale, ceases to operate, and the full freedom of puruṣa occurs. Thus, intelligence and knowledge are not the direct cause of liberation, but by removing ignorance, they are the indirect cause.

Not seeing things as they are is the cause of this phenomenon.

Ignorance of the True Self is the cause of this illusory union.

Its cause is the lack of awareness of his Real nature.

By dedicated practice of the various aspects of yoga impurities are destroyed: the crown of wisdom radiates in glory.

Iyengar Commentary:

Patañjali sums up the effects of yoga in this one sutra. He says that by regular and devoted practice, the impurities of the sadhaka’s body and mind are consumed, the causes of afflictions removed and the crown of wisdom is acquired. This wisdom and achievement keep the sadhaka innocent and free of pride.

Here, instead of the usual word abhyasa (repeated practice), anusthana is used. It is a dignified and noble word with a spiritual import, implying practice with dedication or religious fervour. The former brings stability; the latter develops maturity of intelligence.

Yoga can cure or lessen our physical, mental, moral and spiritual sufferings. Perfection and success are certain only if one practises with love and whole-hearted dedication.

The cause of this union is ignorance.

Satchidananda Commentary:

Here, Patañjali laughs at the idea he has just expressed. The cause of the saṁyoga is ignorance. This may seem a bit confusing, but if we understand it properly there’s no puzzle. You see, in the previous sūtra, we’re still in the world and wondering about the reason for nature. Once the Puruṣa understands itself, it thinks, “How did this union come about? It’s because I’ve forgotten myself. What an ignorant person I was. Because of my ignorance I created this union.” Such a person laughs at it, but this attitude comes only after realization. It’s like a dreaming person who, upon waking, laughs at his or her own frightening dream. The understanding behind this sūtra is a result of realization. Once we realize, we can advise others: “I was ignorant. I had terrible experiences. I thought nature was real, happiness was real. I ran after them. But now I know what they are. I learned the hard way. Do you also want to have to learn the hard way? Why don’t you take my advice?”

These sūtras are reminiscent of the Four Noble Truths of the Buddha: the misery of the world, the cause of misery, the removal of that misery and the method used to remove it. Patañjali tells us that pain can be avoided. He further tells us that its cause is ignorance. In sūtra 26, he gives us another word, hāna, the removal of this misery, and then hānopāya, the method to remove it. We can really see the similarity between the Four Noble Truths and the Yoga Sutras. We needn’t search for who copies whom. Truth is the same always. Whoever ponders it will get the same answer. The Buddha got it. Śri Patañjali got it. Lord Jesus got it. Prophet Muhammad got it. The answer is the same, but the method of working it out may vary this way or that.

Ignorance is its cause.

SV Commentary:

Through ignorance we have joined ourselves with a particular body, and thus opened ourselves to misery. This idea of body is a simple superstition. It is superstition that makes us happy or unhappy. It is superstition caused by ignorance that makes us feel heat and cold, pain and pleasure. It is our business to rise above this superstition, and the Yogi shows us how we can do this. It has been demonstrated that, under certain mental conditions, a man may be burned, yet, while that condition lasts, he will feel no pain. The difficulty is that this sudden upheaval of the mind comes like a whirlwind one minute, and goes away the next. If, however, we attain it scientifically, through Yoga, we shall permanently attain to that separation of Self from the body. 

The effective cause, however, of the conjunction of the individual consciousness with its own Will-to-be is Nescience, which means the potency of the habit of unreal cognition. The Will-to-know, possessed as it is of the aroma of the habits of unreal cognition, does not culminate into the knowledge of the self, which is the end of its work, and thus

having still a duty to perform, comes back. When, however, it reaches the culmination of its work, which is the attainment of the knowledge of the Puru§a, its work is achieved, ignorance is gone, the cause of bondage no longer remains, and it does no longer come back.

Someone ridicules this position by the story of the impotent husband. A foolish wife thus addressed her husband : — “ My dear, my sister has got children. Wherefore have I none ? ” He said to her : — “ I shall beget children unto thee when I am dead.’* Similarly, this knowledge while in existence, does not cause the mind to cease from action ; what hope is there that it will cause cessation when suppressed ? Says on this subject a* teacher very nearly perfect: — “Is not Moksa (freedom) the cessation of the Will-to-be itself and nothing else ? The Will-todbe ceases to act when the cause of ignorance no longer remains. The Ignorance which is the cause of bondage is removed by knowledge. Moksa (perfect freedom) then is only the cessation of the mind from its work. Wherefore then this mental confusion out of place ?