The word Yoga means ‘union,’ and the same root is found in the English word ‘yoke.’ The union in question is that of the human being with the Universal, and the concern of this darshana is to prepare the way for such a union. The formulation of the sutras for this darshana is attributed to Patanjali. While Sankhya was concerned with theoretical preparation, Yoga can be seen as providing the means of realization which complement and complete the theoretical foundation laid by Sankhya. Because Yoga, specifically within the branch of itself called hatha-yoga, deals with preparations and techniques relating to the physical body, we should be careful not to take from this the false idea that its goal pertains to the physical domain. Yoga is not a method for developing ‘the powers of the human organism,’ but merely deals with the human organism so as to put it in its proper place and prepare the way for realization in the metaphysical sense, a realization in which the physical body does not play an effective part. The ‘yoga’ of the West, conceived as a form of ‘spiritualized exercise,’ resembles Hindu Yoga in nothing more than a very particular and most superficial way, and should not really even retain the name.
As we suggested already, Yoga completes Sankhya by introducing the Divine Personality, or Universal Being, called Ishwara. By way of this principle, the apparent dualism of the previous darshana is immediately resolved, since Purusha and Prakriti are unified in Ishwara.
It was seen early that Sankhya, due to its point of view, considered manifestation in order of production, enumerating the elements from the higher to the lower, which was the reverse of Vaisheshika. Here again we must undergo such a procedure, and this is another aspect that sets apart Sankhya from Yoga, even if the two are connected. Because Yoga is wholly concerned with a return to its point of development, it adopts the point of view of the manifested being, and from here it looks to Universal Being, Ishwara, with which it seeks unification. From this point of view, Ishwara is the first principle; but it should be remembered that Ishwara is only first in a relative sense, and that it is Brahma, which alone is beyond Being and therefore beyond Ishwara, that is absolutely first. But because we are at the point of view of the manifested being, it is legitimate to consider Ishwara as the goal.
Because metaphysical realization concerns knowledge, all that is not knowledge is either unnecessary or necessary as a means for obtaining knowledge. This too should put in its place the Western conception of Yoga that reduces it to the most superficial aspect of hatha-yoga, and makes stretching routines its central activity, as if these could lead to anything of value beyond the purely physical. What actually is central to it, and what is its primary ‘means’ of progressing, is called ekagrya, or ‘concentration.’ Any exercises included in its repertoire only have value insofar as they act as a support for this ekagrya; such things, like symbols or other external rites, are nothing more than aids for the goal of contemplation. All such things have use, and should be respected for the support they provide, but in themselves they could not possibly bring about realization, all actions being extraneous to knowledge. What hatha-yoga accomplishes, when effective, is the destruction or transformation of elements in the human being, including the human body, that may form an obstacle to concentration and to union with the Universal. This is does by aiding the being by helping it to assimilate certain rhythms into itself by physical means, such as the control of breathing. It is knowledge alone which can bring about realization, and this is done through dhynana (intellectual contemplation).
In Tibet, there is a notion called the ‘direct path’ or ‘short cut,’ and this refers to those situations where a being is able to skip certain steps on the path to realization and arrives directly at the final goal, or at a certain future point on the way to it. This is the meaning of the term raja-yoga in the Hindu doctrines.
The Yogi is one who has realized perfect union. We should admit, then, that this is not a term that can be applied to one who commits himself to the study of Yoga alone, which does not reach into metaphysics itself, but only to the level of Ishwara. Such an admission is not an insult to the darshana, however, but is again a result of the proper order of things, and the open-endedness of each darshana is able to account for it in an acceptable way, without implying contradiction or error. The Yogi is defined not by any external display of ‘powers,’ which will be dealt with in their turn due to the susceptibility of Westerners to become mesmerized by such things; on the contrary, the true Yogi is simply one who possesses the highest possibilities within himself, and has brought them to their fullest development. As for the ‘supernatural’ powers (siddhis or vibhutis) sometimes seen in these cases, they should not be taken as necessary, nor given undue importance.
Because Yoga, and in particular the hatha-yoga, deal primarily with the preparation for union with the Universal, their place in the order of the darshanas is an appropriate one. The first two lay the groundwork for an understanding of the human mind and nature, the third opening the way to the incorporeal, and Yoga reaching to Being itself. It is at this point, however, that we make contact with pure metaphysics, and it is here that the goal of all these preparations is found. Thus, we may proceed to the final pair of darshanas.