The document is about the Yoga system as propounded by Swami Krishnananda. It provides an overview of some key concepts in yoga psychology.
It discusses that yoga is based on a sound philosophy and deep psychology, aiming to train the human mind to become more natural. It examines the five modes or functions of the internal organ - pramana (right knowledge), viparyaya (wrong perception), vikalpa (doubt), nidra (sleep), and smriti (memory). All thoughts and objects can be reduced or understood through these five types of functions and elements. The document lays out some foundational concepts in yoga to clarify misconceptions and set the stage for understanding this system.