for concentration as described in the _sūtra_ I. 34, where it is said that steadiness is acquired by prāṇāyāma in the same way as concentration, as we also find in the _sūtra_ II. 53. When the senses are restrained from their external objects by pratyāhāra we have what is called pratyāhāra, by which the mind remains as if in its own nature, being altogether identified with the object of inner concentration or contemplation; and thus when the citta is again suppressed, the senses, which have already ceased coming into contact with other objects and become submerged in the citta, also cease along with it. Dharaṇa is the concentration of citta on a particular place, which is so very necessary at the time of prāṇāyāmas mentioned before. The mind may thus be held steadfast in such places as the sphere of the navel, the lotus of the heart, the light in the brain, the forepart of the nose, the forepart of the tongue, and such like parts of the body. Dhyāna is the continuance or changing flow of the mental effort in the object of dharaṇa unmediated by any other break of conscious states. Samādhi, or trance contemplation, results when by deep concentration mind becomes transformed into the shape of the object of contemplation. By pratyāhāra or power of abstraction, mind desists from all other objects, except the one on which it is intended that it should be centred; the Yogin, as he thus abstracts his mind, should also try to fix it upon some internal or external object, which is called dhāraṇā; it must also be noticed that to acquire the habit of dhāraṇā and in order to inhibit the abstraction arising from shakiness and unsteadiness of the body, it is necessary to practise steadfast posture and to cultivate the prāṇāyāma. So too for the purpose of inhibiting distractions arising from breathing. Again, before a man can hope to attain steadfastness in these, he must desist from any conduct opposed to the yamas, and also acquire the mental virtues stated in the niyamas, and thus secure himself against any intrusion of distractions arising from his mental passions. These are the indirect and remote conditions which qualify a person for attaining dhāraṇā, dhyāna, and samādhi. A man who through his good deeds or by the grace of God is already so much advanced that he is naturally above all such distractions, for the removal of which it is necessary to practise the yamas, the niyamas, the āsanas, the prāṇāyāma and pratyāhara, may at once begin with dhāraṇā; dhāraṇā we have seen means concentration, with the advancement of which the mind becomes steady in repeating the object of its concentration, i.e. thinking of that thing alone and no other thing; thus we see that with the practice of this state called dhyāna, or meditation, in which the mind flows steadily in that one state without any interruption, gradually even the conscious flow of this activity ceases and the mind, transformed into the shape of the object under concentration, becomes steady therein.