We have discussed this subject in another chapter. Here we pick up some relevant verses from Samkhya.
Bodies born of parents: consists of six sheaths. Among these six hair, blood, flesh come from mother. Arteries, bones, and marrow come from father. Specific: Subtle body, bodies from parents, and gross elements are three specific objects.
Subtle body always remains, and it incarnates again and again. Therefore there is no escape from the cycles of life. This is consistent with the Gita verse [G.2.27] which says a soul that takes birth will die, and who dies will always be born again.
Subtle body is composed of Intelligence, I-Principle, Mind, 5 sense organs, 5 action organs, and 5 primary elements. Subtle body is created by soul using root materials from nature. Unconfined: moves everywhere. The subtle body is unobstructed and can pass through mountains. Primordially: When universe is uncreated the subtle body is created first.
It is constant, because it continues to exist forever. Only subtle body incarnates, gross body perishes. Experience: Subtle body cannot acquire any experience without the gross body. That is why it migrates and acquires new gross body to acquire more experience.