184. The Buddhi with its modifications and the organs of knowledge, forms the Vijnanamaya Kosha or knowledge sheath, of the agent, having the characteristics which is the cause of man’s transmigration.
185. This knowledge sheath, which seems to be followed by a reflection of the power of the Chit, is a modification of the Prakriti, is endowed with the function of knowledge, and always wholly identifies itself with the body, organs, etc.
186-187. It is without beginning, characterised by egoism, is called the Jiva, and carries on all the activities on the relative plane. Through previous desires it performs good and evil actions and experiences their results. Being born in various bodies, it comes and goes, up and down. It is this knowledge sheath that has the waking, dream and other states, and experiences joy and grief.
188. It always mistakes the duties, functions and attributes of the orders of life which belong to the body, as its own. The knowledge sheath is exceedingly effulgent, owing to its close proximity to the Supreme Self, which identifying Itself with it suffers transmigration through delusion. It is therefore a superimposition on the Self.
189. The self-effulgent Atman, which is Pure Knowledge, shines in the midst of the Pranas, within the heart. Though immutable, It becomes the agent and experiencer owing to Its superimposition, the knowledge sheath.
190. Though the Self of everything that exists, this Atman, Itself assuming the limitations of the Buddhi and wrongly identifying Itself with this totally unreal entity, looks upon Itself as something different – like earthen jars from the clay of which they are made.
191. Owing to Its connection with the super-impositions, the Supreme Self, even thou naturally perfect (transcending Nature) and eternally unchanging, assumes the qualities of the superimpositions and appears to act just as they do – like the changeless fire assuming the modifications of the iron which it turns red-hot.
192. The disciple questioned: Be it through delusion or otherwise that the Supreme Self has come to consider Itself as the Jiva, this superimposition is without beginning, and that which has no beginning cannot be supposed to have an end either.
Source: Vivek Choodamani