What is the 'causal body' described in the text, and how can one be free from it?

The text in Chapter 50 explains that the 'causal body' (karana) of the soul is also known as the 'Unmanifest' (Avyakruta). It is described as being imbued with a reflection of consciousness and is considered the cause of pure ignorance. The root of this causal body is the Soul's own ignorance. To achieve liberation from it, one must attain the knowledge of the unity of Brahman and the Soul. The text emphasizes that the removal of this body happens only through this specific knowledge. This ultimate state of freedom, where one abides in one's own true form, is what is given the name 'liberation' or Moksha.