Atman

Atman, in both Hinduism and Buddhism, refers to the human soul. While Hindus believe that the soul represents the life-force within all human beings and animals which survives death in a cycle of reincarnation, Buddhists believe that no such soul exists, a doctrine referred to as anatman. In some schools of Hinduism, such as Advaita Vedanta, it is held that atman is fully identical to Brahman, the supreme monistic principle or deity, while other schools such as Visistadvaita and Dvaita Vedanta, claim that this is only partially true or not true at all, respictively.

Hinduism

Early History

While the Vedic texts largely describe an external religious tradition of sacrifice and other ritualism, the commentaries upon these texts, the Upanishads (ca. 900 B.C.E.), turn the focus inward. Included within this new intrinsic religious perspective is a detailed discussion of the Self. Upanshadic thinkers characterize the self in a number of ways, describing it as food, will, consciousness and breath, among other things, though none of these was truly satisfactory. Atman is most profoundly described as the eternal person which is never born and never dies, lasting throughout eternity through a continual process of reincarnation. The ... Upanishad describes this eternal self as "the shining, immortal person." The motivation of religious activity, then, is to free oneself from the baneful material world in order to liberate the soul from the cycle of rebirth. As the Chandogya Upanishad explains:

The self which is free from sin, free from old age, from death and grief, from hunger and thirst, which desires nothing but what it ought to desire, and imagines nothing but what it ought to imagine, that it is which we must search out, that it is which wew must try to understand. He who has searched out that Self and understands it, obtains all worlds and desires (Chandogya Upanishad VIII:7:1).

Bliss, then, awaits the individual who realizes the true nature of their self.

Atman and Brahman

Perhaps the most famous claim made in the Upanishads is that atman is the very same as Brahman. In this sense, the human soul is a microcosm of the pervasive divinity that forms the ground of the universe. The ninth chapter of The Taittiriya Upanishad reports this as follows: "He who knows the Bliss of Brahman, whence words together with the mind turn away, unable to reach It? He is not afraid of anything whatsoever. He does not distress himself with the thought: 'Why did I not do what is good? Why did I do what is evil?'. Whosoever knows this regards both these as Atman; indeed he cherishes both these as Atman. Such, indeed, is the Upanishad, the secret knowledge of Brahman." In the years that followed, the three schools of Vedanta ("end of the Vedas') provided varied interpretations of the relation of Brahman and atman based on statements such as these.

Advaita Vedanta

Advaita (or "non-dualistic") Vedanata was the first of the Vedanta schools, garnering its name from the dualism it denies between atman and brahman. Shankara (788-820 C.E.), the famous Hindu mystic philsopher who developed the Advaita philosophy, interpreted the Upanishadic connection between brahman and atman to be one of essential oneness. The Self is brahman, indistinguishable from the supreme reality suggested from which it derives. For Shankara, the entirety of the universe except for the highest, indescribable form of Brahman, is an illusion (or maya). Perceived differences between god and the individual soul are created by the erroneous perception of particulars in the physical world. Once one eschews all distinctions of the particular things in the illusory physical, Shankara believe they could then come to realize that atman is brahman. Only then can they escape maya and merge into oneness with Brahman.