Prakriti-Purusha Viveka Yoga is the thirteenth chapter of the Bhagavad Gita, which discusses the distinction between Prakriti and Purusha. In this chapter, Lord Krishna explains to Arjuna the nature of the Purusha (the supreme consciousness) and the Prakriti (material nature).
Lord Krishna explains that the Purusha is eternal, unchanging, and indestructible. It is the consciousness that is present in all living beings and is the ultimate reality. On the other hand, Prakriti is the material nature that is constantly changing and is composed of the three gunas – Sattva, Rajas, and Tamas.
Lord Krishna advises Arjuna to understand the difference between the Purusha and Prakriti, and to realize that the Purusha is the source of all knowledge, happiness, and liberation. He also emphasizes that the ultimate goal of life is to realize the Purusha and attain liberation from the cycle of birth and death.
This chapter also discusses the various paths to attain knowledge of the Purusha, such as meditation, austerity, and self-discipline. Lord Krishna emphasizes that by following any of these paths with devotion and dedication, one can attain the knowledge of the Purusha and ultimately attain liberation.