Chapter 19 describes a hierarchy of subtlety leading to the Pure Brahman. Can you outline this spiritual progression?

In a profound philosophical passage, Chapter 19 outlines a progression of subtlety from the individual soul to the ultimate reality. It begins with the Soul (Atma), which is described as a Great Power. Subtler than the Soul is the Unmanifest (Avyakta), which is also referred to as Space or Maya. Moving to an even subtler level, the text introduces the Purusha, or the Supreme Being. This Purusha is described as the ultimate goal where the senses and mind finally find rest. As Chapter 19 concludes, this final state is identified as the Pure Brahman, the ultimate, changeless reality.