Tantra (Sanskrit: तन्त्र, “loom, warp”; hence “principle, system, doctrine, theory”, from the verbal root tan ”stretch, extend, expand”, and the suffix tra“instrument”), anglicised as tantrism or tantricism, is the name scholars give to a style of religious ritual and meditation that arose in medieval South Asia no later than the fifth century CE, and which came to influence all forms of Asian religious expression to a greater or lesser degree. Strictly speaking, this usage of the word “tantra” is a scholarly invention, but it is justifiable on the basis of the fact that the scriptures that present these practices are generally known as “tantras“, regardless of which religion they belong to.
The historical significance of the Tantric method lies in the fact that it impacted every major Asian religion extant in the early medieval period (c. 500 – 1200 CE): thus Shaivism, Buddhism, Vaishnavism, and Jainism all developed a well-documented body of Tantric practices and related doctrines. EvenIslam in India was influenced by Tantra. Tantric ideas and practices spread far outside of India, into Tibet, Nepal, China, Japan, Cambodia, Vietnam, and Indonesia.  Today, it is Tibetan Buddhism and various forms of Hinduism that show the strongest Tantric influence, as well as the internationalpostural yoga movement and most forms of American alternative spirituality grouped under the New Age rubric.
Defined primarily as a technique-rich style of spiritual practice, Tantra has no single coherent doctrine; rather, it developed different teachings in connection with the different religions that adopted the Tantric method. These teachings tended to support and validate the practices of Tantra, which in their classical form are more oriented to the married householder than the monastic or solitary renunciant, and thus exhibited what may be called a world-embracing rather than a world-denying character. Thus Tantra, especially in its nondual forms, rejected the renunciant values of Patañjalian yoga, offering instead a vision of the whole of reality as the self-expression of a single, free and blissful Divine Consciousness under whatever name, whetherŚiva or Buddha-nature. Since the world was viewed as real, not illusory, this doctrine was a significant innovation over and against previous Indian philosophies, which tended to picture the Divine as absolutely transcendent and/or the world as illusion. The practical consequence of this view was that not only could householders aspire to spiritual liberation in the Tantric system, they were the type of practitioner that most Tantric manuals had in mind. Furthermore, since Tantra dissolved the dichotomy of spiritual versus mundane, practitioners could entail every aspect of their daily lives into their spiritual growth process, seeking to realize the transcendent in the immanent. Tantric spiritual practices and rituals thus aim to bring about an inner realization of the truth that “Nothing exists that is not Divine” (nāśivaṃ vidyate kvacit), bringing freedom from ignorance and from the cycle of suffering (saṃsāra) in the process. Though the vast majority of scriptural Tantric teachings are not concerned with sexuality, in the popular imagination the term tantra and the notion of superlative sex are indelibly, but erroneously, linked. This error probably arose from the fact that some of the more radical nondual schools taught a form of sexual ritual as a way of entering into intensified and expanded states of awareness and dissolving mind-created boundaries.
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