all knowable things are the products of prakṛti. All knowledge thus requires the presence of the overseer, puruṣa, and of something seen, an object in prakṛti.
This passage establishes the Sāṃkhya-Yoga thesis that Prakrti is the totality of objectifiable reality, and that every act of knowing presupposes an observer distinct from it, with the ego’s false conflation of seer and seen constituting the primary error.
, The Yoga Sutras of Patanjali: A New Edition, Translation, and Commentary, 2009thesis