Koshas (Five Sheaths)

The outermost sheath: the gross body built from anna (food). It is born of food, sustained by food, and at death returns to food — Taittirīya II.1 calls it the puruṣa shaped 'with the head, the right wing, the left wing, the trunk, and the tail' of an embodied bird. In the kośa schema it is the densest envelope, the field of metabolism and physical form, and the obvious anchor a contemplative begins from before discriminating the subtler four. It is real but not Self. The classical move (Vivekacūḍāmaṇi 154–164) is to recognise that the body changes, sleeps, ages, dies, and yet awareness of it persists; therefore the body is an object of knowing, not the knower.

The vital sheath, woven of the five prāṇas (prāṇa, apāna, vyāna, udāna, samāna). Taittirīya II.2 says the food-body is filled by this prāṇa-body 'as a body is filled by self' — the breath-body has the same shape as the food-body, and gives it animation. Yogic anatomy locates its main currents in the thoracic cavity and along the central axis; in haṭha and tantric sources it threads the nāḍīs and is governed by the breath at the heart. It is the first sheath that is not directly perceptible. You can feel its presence as the difference between a living body and a corpse of the same shape.

The mental sheath: manas, the field of saṅkalpa-vikalpa (assertion and doubt), of sense-impressions and the chatter of intention. Taittirīya II.3 describes it filling the prāṇa-body with the same human form. Vedānta classes it with the lower mind — reactive, ruled by the indriyas — and locates it conventionally at the throat-and-head axis where speech, hearing, and discursive thought concentrate. It is the sheath in which the Vedas, mantras, and ritual instructions are received and rehearsed. Discrimination begins here but does not end here.

The sheath of buddhi — discriminative knowing, the witness-near intelligence that decides, doubts in a higher register, and resolves. Taittirīya II.4 places it inside the manomaya, with the same shape; it is the agent of yajña — every act becomes a sacrifice once buddhi is awake. In Advaita this is the sheath most easily mistaken for the Self, because its clarity feels like presence itself. The teaching insists: even buddhi is an object lit by the witness — it sleeps in deep sleep, the witness does not.

The innermost sheath, ānandamaya — made of bliss. Taittirīya II.5 calls it the inmost shape filled by joy as its head, by satisfaction as its right wing, by great-joy as its left wing, and by Brahman as its tail and supporting ground. It is associated with the cave of the heart (hṛd-guhā) where deep sleep dissolves discursive mind into undifferentiated rest. Classical Advaita is precise: ānandamaya is still a kośa — a covering. Brahman is its support, not its synonym. The contemplative passes through, not into, this last veil.