What is the distinction between 'Vidya' and 'Avidya', and how does it relate to the cycle of birth and death?

Chapter 37 explains that the path one follows is determined by their focus on either 'Vidya' (knowledge) or 'Avidya' (ignorance). Avidya is defined as that which has only 'Preyas' (the pleasant) as its subject. It is the root cause of all suffering, establishing the perception of manifoldness and duality, which leads to constant worry and binds one to the cycle of birth and death. Conversely, Vidya is that which has 'Shreyas' (the ultimate good) as its subject. By acquiring this true knowledge through the scriptures and the Guru, one removes ignorance. Once ignorance is gone, the perception of difference ceases, and the cycle of birth and death ends for that individual.