Though the higher reaches of meditation are inseparable from what are known as samapattis or samadhis in the language of Patanjali, a logical distinction can be made between the two in the sense that dhyana or meditation is constituted of the threefold process mentioned, and in samadhi the whole process gets united with the object, comparable in some way to the entry of a river into the ocean, in which condition the river ceases to be what it was and becomes the ocean itself. Here Patanjali has an interesting thing to tell us, viz., that in this condition the percipient, the object and the medium or the process of perception stand parallel to one another, on an equal status, as if three lakes or tanks of water merge into one another, mingling one with the other, with water in every one filled to the same level on the surface. The three have become one, and one cannot know which is the subject, which the object and which the process of knowing. 

The act of meditation leads to the attainments known as samapattis. While the object chosen for purpose of meditation can be any particular unit or entity, whether perceptual or conceptual, the final requirement is an absorption of consciousness in the structure of the cosmos itself, which is constituted of the five great elements or mahabhutas,-earth, water, fire, air and ether. 

Patanjali speaks of vitarka, vichara, ananda and asmita stages in these attainments, which are again sub-divided into the stages known as savitarka, nirvitarka, savichara, nirvichara, sananda and sasmita. These samapattis are the graduated attunements of the meditating consciousness with the cosmological categories enumerated in the Samkhya philosophy. The lowest forms of the manifestation of prakriti are the five elements mentioned, which in their gross form enter into every minor form of the world, constituting the diversity of the objects of sense perception and mental cognition. 

Patanjali has a specific recipe to enable the mind to contemplate upon the object as such in its pure form, divested of the phenomenal associations it is involved in as an object of sensory perception. When we speak of an object, for instance, we mean thereby a blend of an idea and a descriptive characteristic going together with the thing-in-itself, which cannot be known except as clothed in the idea of it and the form in which it is perceived. Here we are reminded of a similar enunciation by the German philosopher Immanuel Kant who ruled out the possibility of knowing things-in-themselves apart from phenomena conditioned by space, time and what he called the categories of the understanding, such as quantity, quality, relation and modality. This is the reason, perhaps, why he did not conceive of it being practicable even to have a metaphysic of reality, because all knowledge is phenomenal, limited to space, time and the categories. Kant held that the ideas of God, freedom and immortality act merely as regulative principles working through the reason but cannot become objects of the reason since its operations are limited to phenomena. Here the Indian sage scores a mark which the philosopher of the Critique could not envisage, viz., that it is possible, nay, it is necessary, that the thing-in-itself has to be known, not merely by actual contact in a process of knowledge, but in union with it, which is yoga proper. The words which Patanjali uses to designate the phenomenal categories are sabda and jnana, and the thing-in-itself is artha. The aim of yoga is to unite consciousness with the thing-in-itself, i.e., with artha. Though, under normal conditions, it is not possible to contact the object as such because of the interference of space and time and the logical categories of the mind, there is a way unknown to logical philosophy, by which the subject and the object can become one, attain yoga or union, which is the perfection of experience. 

In the savitarka samapatti the object or artha is contemplated upon as involved in sabda and jnana, its name and idea. But this is a different kind of awareness from that which obtains in ordinary perception of things, for, in a samapatti there is an absorption of consciousness in the contemplated object, and the form does not any more remain as an external object to be contacted by sensory activity even in this state of a threefold involvement. In the higher stage known as nirvitarka samapatti, the physical form of the object, independent of sabda and jnana, is the object of absorption. Here the object may be taken as the whole physical universe of five elements, or any particular object chosen for the purpose of meditation. In the cosmological enumeration of the categories of the Samkhya, the evolutes which are higher than the five physical elements are the five tanmatras, or subtle potentials of these elements, known as sabda, sparsa, rupa, rasa and gandha, which mean respectively sound, touch, form, taste, and smell, as the objects of experience. When these tanmatras become the objects of meditation, or rather, absorption, as envisaged in terms of space and time, the attainment is known as savichara samapatti. When the same become objects of absorption independent of and transcendent to space and time, the experience is called nirvichara samapatti. By the time this stage is reached by the yogin, a complete mastery is attained over the elements and the forces of Nature, and a perfection ensues which brings immense joy, not born of contact with anything, but following as a result of the attainment of freedom by union with the Cosmic ahamkara, and mahat, which are the omniscient and omnipresent Ground of the whole universe. This joy is an attainment know as sananda samapatti, when the experience reaches its heights and the entire universe is known as One's own Body and not as an object of perception any more, when there is no such thing as a universe, but a pure Cosmic Experience-Whole in which the Cosmic Subject is in union with the Cosmic Object. There is a realization of the Absolute-'I'. This Universal Self-Experience is known as sasmita samapatti. 

All the six stages of samapatti stated above come under what is known as sabija samadhi or union with the remnant of a seed of Self-Consciousness though of a Universal Nature. When even this Self-Consciousness is transcended and only the Absolute reigns supreme in experience par excellence, there is nirbija samadhi, or the seedless attainment of Supreme Independence. The Final Attainment thus experienced is kaivalya moksha, or utter Freedom in the Absolute Reality.