Kosha

A Kosha (also Kosa; Sanskrit , IAST: kośa), usually rendered "sheath", is a covering of the Atman, or Self according to Vedantic philosophy. There are five Koshas, and they are often visualised as the layers of an onion.

The five sheaths (pancha-kosas) are described in the Taittiriya Upanishad. From gross to fine they are:

According to Vedanta the wise person, being aware of the subtle influences of the five elements within each kosha, ever discerns the Self amidst appearances.

This is the sheath of the physical self, named from the fact that it is nourished by food. Living through this layer humans identify themselves with a mass of skin, flesh, fat, bones, and filth, while the human of discrimination knows their own self, the only reality that there is, as distinct from the body.

Pranamaya means composed of prana, the vital principle, the force that vitalizes and holds together the body and the mind. It pervades the whole organism, its one physical manifestation is the breath. As long as this vital principle exists in the organisms, life continues. Coupled with the five organs of action it forms the vital sheath. In the Vivekachudamani it is a modification of vayu or air, it enters into and comes out of the body.

Manomaya means composed of manas or mind. The mind (manas) along with the five sensory organs is said to constitute the manomaya kosa. The manomaya kosa, or “mind-sheath” is said more truly to approximate to personhood than annamaya kosa and pranamaya kosha. It is the cause of diversity, of I and mine. Sankara likens it to clouds that are brought in by the wind and again driven away by the same agency. Similarly, man’s bondage is caused by the mind, and liberation, too, is caused by that alone.

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