Psychologically, as long as we remain locked within a specific frame of reference, we are unable to see the larger picture within which that frame operates, with any amount of objectivity. The subtle assumptions and axiomatic ideas lock us into a way of seeing and reacting that is consistent with that frame. The Sankhya tradition recognized this psychological truth and developed the powerful tool of the separation of Purusha and Prakriti as a means to gain a degree of independence from the reactions and impulsions 0f Nature; thereby eventually permitting the individual applying this standpoint to achieve sufficient independence to be able to view and understand the actions of the external nature, and eventually escape from their hold.
Sri Aurobindo describes the power of this stage of the yogic process: “The initial advantae of this process of detachment is that one begins to understand one’s nature and all Nature. The detached Witness is able to see entirely without the least blinding by egoism the play of her modes of the Ignorance and to pursue it into all its ramifications, coverings and subtleties–for it is full of camouflage and disguise and snare and treachery and ruse. Instructed by long experience, conscious of all act and condition as their interaction, made wise of their processes, he cannot any longer be overcome by their assaults, surprised in their nets or deceived by disguises. At the same time he perceives the ego to be nothing better than a device and the sustaining knot of their interaction and, perceiving it, he is delivered from the illusion of the lower egoistic Nature.”
This detachment is the leverage needed to free the seeker from all forms of egoism, whether based in tamas, rajas or sattwa. “Thus convinced and conscious of the essential vice of the ego-sense in all our personal action, he seeks no longer to find a means of self-correction and self-liberation in the rajasic or sattwic ego but looks above, beyond the instrument sand the working of Nature, to the Master of works alone and his supreme Shakti, the supreme Prakriti. There alone all the being is pure and free and the rule of a divine Truth possible.”
The establishment of the inner separation of Purusha from Prakriti, the Witness from the executive Nature, is a key technique to both establish the independent standpoint that can lead systematically to liberation from the bondage of the Gunas of Nature and free the seeker from the knot of the ego-consciousness.
Sri Aurobindo, The Synthesis of Yoga, Part One: The Yoga of Divine Works, Chapter 10, The Three Modes of Nature, pp. 226-227