Karana Sharira — The Causal Body and Deep Sleep
The Karana Sharira (causal body) is the subtlest of the three bodies in Advaita — the seed form of ignorance (Avidya) that generates the subtle and gross bodies — experienced partially as the bliss of deep sleep.
Advaita Vedanta describes three bodies (Shariras) that the Atman appears to inhabit: the Sthula Sharira (gross/physical body), the Sukshma Sharira (subtle body of mind, intellect, and vital forces), and the Karana Sharira (causal body). The Karana Sharira is the most subtle — it is not a body at all in any ordinary sense but the seed-form of Avidya (ignorance) from which the other two bodies grow. It corresponds to the state of deep sleep (Sushupti) — where the physical and subtle bodies dissolve into undifferentiated potential. In deep sleep, the individual self appears to dissolve (the ego and its concerns temporarily cease), and what remains is a state of undifferentiated peace — which is why deep sleep is refreshing: the Ananda of Brahman is tasted without the filter of individual ego. But this is not liberation — because upon waking, the Karana Sharira reconstitutes the subtle and gross bodies. Liberation requires the dissolution of the Karana Sharira itself (the seed of ignorance), which only Brahma Jnana achieves.
The causal body is the seed of all ignorance — its dissolution in the fire of Brahma Jnana is liberation.
Sleep researcher Matthew Walker's 'Why We Sleep' documents the crucial restorative functions of deep sleep (NREM) — including memory consolidation, emotional processing, and cellular repair — consistent with the Advaita teaching that deep sleep represents a partial dissolution of the individual's constructed experience.
Vivekachudamani
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- What Advaita Vedanta says about illness and the body failing
Advaita points at deep sleep, where the body and its troubles drop out and something remains that finds the absence restful. That nightly evidence is used to argue you are not exhausted by the body's condition. The tradition is honest that this is not liberation: the seed of ignorance reconstitutes on waking.