The origins of the Yoga tradition are unknown to us, but there is a commonly stated view that it dates back at least 5000 years, although it is possible that ongoing archaeological research could provide evidence of an even earlier presence. Given the length of time involved, it is useful to consider the history of Yoga in terms of six periods: Proto, Pre-Classical, Epic, Classical, Post-Classical and Modern. The dating of most of these periods is only approximate, as it is based on the presumed age of significant Hindu texts.

Proto-Yoga
The Proto-Yoga period has its beginnings in the prehistory of India and extends to about 1500 BCE. What we know of this period comes from two main sources: archaeological findings such as statues and seals with images of individuals in what seems to be yoga postures from the pre-Vedic Indus Valley civilisation, and references in the earliest and most important of the sacred texts of Hinduism, the Vedas. The Proto-Yoga of the Vedas seems to have been an unsystematic collection of practices that included concentration, regulation of the breath, austerities, devotional invocations and significantly, an aspiration for a reality that exceeds the limitations of sense-bound experience.

Pre-Classical
The Pre-Classical period takes us to around 500 BCE and consists of the first detailed articulations of what we recognise today as yogic principles and practices in the early Upanisads. The Upanisads are considered to be the first truly philosophical texts of the Hindu tradition, and even though they do not put forward a single coherent doctrine, the essence of their teachings is captured in this passage from the Brhadaranyaka Upanisad (3.4.2).

Epic
The Epic period spans the centuries from around 500 BCE to 200 CE and involves the Yoga of the middle Upanisads and the great epic the Mahabharata which includes the revered scripture the Bhagavad-Gita. The Katha Upanisad provides the first explicit expression of the fundamental principles of yogic practice.

The Bhagavad-Gita is a remarkable synthesis of the diverse threads of spiritual thinking of the Epic period, and remains a source of wisdom and inspiration for spiritual aspirants. Most characteristically, the Bhagavad-Gita brings together the three most fundamental paths of yoga: Jnana, Bhakti and Karma, within a framework that emphasises the inner renunciation of the fruit of one’s actions through a complete surrender to the Lord.

Classical
The Classical period marks the systemisation of yoga in Patanjali’s Yoga-sutra. In historical terms, the Classical system of Patanjali is the most significant of the many schools of yoga, and is included among the six orthodox darsanas or philosophical systems of Hinduism. Tradition identifies Patanjali with the famous grammarian of the second century BCE, and also asserts that he was an incarnation of the Lord of serpents, Adisesa or Ananta, who is often represented as the couch on which Lord Visnu reclines. However scholars tend to place the Yoga-sutra in the second century CE, which means that either the text we have is a later version, or that the grammarian and the yogin are not the same person. The Yoga-sutra has been the subject of many extensive commentaries, the most notable being the Yoga-Bhasya of Vyasa (c. 5th century CE) and the Tattva-Vaisaradi of Vacaspati (c. 9th CE), and it remains the focal text for many schools of Yoga today. Patanjali’s yoga is also known as Classical-, Raja- and Astanga-yoga, the last term referring to the eight ‘limbs’ or facets which characterise this arrangement and codification of earlier forms of Yoga.

Post-Classical
The development of Yoga in the Post-Classical period (c. 200 – 1900 CE) was greatly influenced by the spread of Tantra throughout India from about the third or fourth centuries CE. Tantra distinguishes itself among Indian traditions by its reverence for the body as an instrument of liberation. The Tantric principle that the Absolute could be realised in and through the human body prepared the ground for the emergence of Hatha-yoga around 1000 C.E., which is the most widely disseminated and commonly practiced form of yoga today. The Yoga Upanisads belong to this period, as do the three most popular Hatha-yoga manuals, the Hatha-Yoga-Pradipika, the Gheranda-Samhita and the Siva-Samhita, all of which bear the influence of Tantrism. To this period also belongs the spread of the bhakti (devotional) movements of Vaisnavism and Saivism, as well as the decline of Buddhism and the subsequent rise of Vedanta as the dominant philosophical position in India.

Modern
The Modern period is best characterised by the dissemination of Yoga and Indian spirituality generally to the world at large. The initial translation of several important Hindu sacred texts took place in the 1800s and several figures such as Swami Vivekananda lectured in North America and Europe towards the end of that century. A succession of Indian gurus followed Vivekananda’s example and established centres in a number of Western countries. These included Paramahansa Yogananda, the author of the widely read Autobiography of a Yogi and founder of the Self-Realization Fellowship, Maharishi Mahesh Yogi’s Transcendental Meditation, Srila Prabhupada’s International Society for Krishna Consciousness (ISKON), and a number of styles of Hatha-yoga such as those promoted by disciples of Swami Sivananda (Swamis Satyananda, Satchidananda and Vishnu-devananda), and later students of Sri Krishnamacharya (B.K.S. Iyengar, K. Patabhi Jois and T.K.V. Desikachar). At the same time, the number of spiritually curious Westerners travelling to and studying in India has continued to increase, and their influence on the directions taken by yoga in the West is growing. Not surprisingly, the development of yoga in India has in turn been effected to some extent by Western ideas, the most notable example being the evolutionary cosmogony that underpins the Integral Yoga of Sri Aurobindo.

Derivation
As with many important Sanskrit terms, the word yoga has diverse meanings in different contexts and historical periods. It is thought to derive from the verb root yuj, whose primary meanings are to yoke, join, harness, attach, bind, join or unify. The derivative noun yoga itself also has a variety of meanings, including exertion, endeavour, zeal, diligence, attention, application or concentration of the thoughts, abstract contemplation, meditation, manner, method, means, device, way, application, performance, combination, connection, contact, and union. In the sense we are interested in here, though, yoga has come to mean both the state of oneness or union with the Absolute, or God, and the various paths and practices whose aim is the realisation of that state.

In a more restricted sense, and as mentioned above, yoga also refers to the Classical system of Patanjali which is one of the six darsanas (from drs, ‘to see’) of Hinduism, the other five being Samkhya, Vedanta, Mimamsa, Vaisesika and Nyaya. The definition of yoga as both union with the Divine and the means towards that end reflects the pervasive influence of Vedanta’s non-dualism. However Patanjali’s conception of liberation (kaivalya or aloneness) follows Samkhya in seeking the irrevocable separation of the Self (purusa) from the manifest world (prakrti). This is best conceived not as a yoking or a union, but as the dissolution of the bonds that tie purusa to prakrti; as the end of the conjunction of the seer and the seen. Vacaspati takes up this issue in his Tattva-Vaisaradi, arguing that what Patanjali meant by yoga wasn’t yoking, binding or conjunction, but meditative concentration. Thus for Patanjali the primary meaning of yoga is the meditative absorption of samadhi, which is the final ‘limb’ of his eightfold path.

Many Paths
The Sanskrit literature also contains many compounds that end in –yoga, some of which have mentioned already: for instance, Raja-yoga, Jnana-yoga, Karma-yoga, Bhakti-yoga, Hatha-yoga, Mantra-yoga, Buddhi-yoga, Laya-yoga, Kriya-yoga, Kundalini-yoga and Nada-yoga. These compounds represent diverse approaches or emphases, and promote particular conceptions of liberation as well as what is believed to be the most effective means to that goal.

Despite the diversity in both the means and the conceptions of the goal, these approaches or paths to spiritual liberation share two important aspects: the cultivation of vairagya or nonattachment to the attractions and aversions of sensory experience, and abhyasa or the continued effort and constant practice required to overcome habits of thought and action that tie us to the senses. As the following quote from Vyasa’s commentary on the Yoga-sutra suggests, taken together vairagya and abhyasa develop an individual’s capacity to discriminate between the true and the false (viveka) in an ultimate sense.

The various paths and approaches recommend practices that have evolved in particular historical, cultural and philosophical contexts, yet also seem to direct themselves to individual temperaments and aptitudes. Thus we find in Jnana-yoga the development of the intellect; in Bhakti-yoga the emotional force of devotion is harnessed; in Karma-yoga active participation in life provides an opportunity to surrender all attachment to the fruit of one’s actions; in Raja-yoga the mind is calmed through concentration and meditation; while in Tantric approaches such as Hatha-yoga there is a focus on the refinement and transformation of the body and its subtle energies.

Ultimately what is important is not the form of the practices adopted, but the sincerity and dedication with which they are undertaken. The real value of any practice is that of a means to an end, and once that end has been realised the practices themselves become redundant. Indeed in rare individuals such as Ramana Maharshi, yoga is realised without recourse to a spiritual discipline of any kind.