Etymologically,  yoga means yoke or union. Academically, it is one of the six orthodox systems  of Indian philosophy founded by the sage Patañjali. Spiritually, it is twinning  of  the finite self and the infinite self,  an interface between the human mind and the cosmic mind, a convergence of  human consciousness and the cosmic  consciousness. In mystic terms, Yoga is merging of prana vayu, the vital air which moves upwards, and apana vayu, the vital air which moves  downwards.

Yoga is  a religious, philosophic, esoteric and scientific  pathway to health, happiness and bliss as it harmonizes mind, body and spirit. Patanjali’s yoga is called Ashtanga  yoga as it has eight limbs, namely, yama (moral  restraints), niyama (principles), asana (bodily postures), pranayamma (breath control), pratyahara(withdrawal of senses from  objects), dharana ( attention), dhyana(right concentration) and samadhi (absorption).

Preliminary  yoga (kriya yoga) is mortification,  study and resignation to  ishwara-god, as per the Yoga Sutra (II.1).Yoga can be bahiranga, that which involves external  practices, like asana and pranayama, and antaranga, that which involves inner practices, like dharana, dhyana and samadhi.

The yoga  of making the body a fit instrument for inner transformation or for attaining siddhis, superhuman powers, is Ha?ha yoga; of gaining insight or direct  self-perception (aparok?anubhuti)  through understanding and conscious reasoning is Jñana yoga; of divine love, devotion or of total surrender to god  is Bhakti Yoga; of righteous action  free of egocentricity is karma yoga; of  controlling the fluctuations of the mind and stabilizing it in god  consciousness, is Raja yoga.

While the  mind is made to follow breath through pranayama in Ha?ha yoga, breath naturally follows  the mind in Raja yoga. One is  oblivious of both the mind and breath in Bhakti yoga, but is aware about the  mind and its relation to breath in Jnana yoga. The mind and breath conjoin in  Karma yoga.

Mantra  joins the rhythm of breath with the rhythm of words. Repetition or chanting of  a  sacred   syllable or  verbal expressions revealed  to sages, seers or ardent devotees of gods, bhaktas,  is Mantra yoga. Mantra is the sound body of the Supreme Principle just as Yantra  is His diagrammatical representation.

Concentration  on the self within or on an external object leading to absorption into the transcendental  principle is Laya yoga. When one is absorbed in the unstruck sound (anahatanada) one gradually reaches the  substratum of sound.

The technique  to rouse latent powers within, by way of physical exercises, breath control,  repetition of mantras, meditation, esoteric practices, or through the  grace of guru,  is Kundalini Yoga. Another popular form,  called Surat shabda yoga, is the practice of joining soul consciousness(surat) with the word (shabda) which epitomizes divine  consciousness. Shiva yoga practiced by the Lingayats (Virashaiva) stirs up ‘the  higher astral sense’. The seeker places Ishtalinga, mark of personal god, that  is worn round  the neck, on the palm  of left hand and fixes attention upon the  light reflected in it.

Yoga is  a purifier, cleanser and energizer. Hatha yoga detoxifies the body and the  mind. Karma yoga purifies actions. Raja yoga stabilizes the mind and elevates  consciousness. Bhakti yoga channelizes emotions. Jnana yoga empowers viveka, sense of discrimination between  right and wrong . All these and other yogas, in their own way, reduce stress,  promote creativity and bring joy.  The  practice of Yoga curbs the animal instincts of a sadhaka – one who is on the yogic path - and kindles in him the  higher values of life.

The yogi undergoes three stages: that of a mumuk?u when he is inquisitive about the  yogic discipline; that of a yoga-yukta when he gains theoretical perspective of the yogic path and initiates the journey and finally that of a vinishpanna when he attains bliss by  becoming one with the One. Thereby, he attains to  the state of turiya.

Turiya  is the fourth dimension of consciousness when the human soul after transcending  the states of wakefulness (jagrata), dream,  (svapna) and deep sleep (sushupti), feels one with the supreme  spirit. Yoga brings infinity closer to a seeker, making him understand the fundamental unity in the cosmos between matter, mind  and consciousness.

The author is a Educationist, historian and spiritualist  of eminence and a former British Council Scholar.

The article was first published in the  journal of the Bhartiya Vidya Bhawan.