Four chapters. The first chapter is called agama, which literally means wedes. In the first chapter are a few caricas along with the 12 mantres. There are comments in sanscrit on both of them by shankara charya. Second chapter uses only logic and experience to prove that non duality is real. Third chapter shows that world of duality we experience is false. Fourth chapter takes up many different points of view from various philosophical schools.
Swami Sarvapriyananda teaches one of the shortest and most profound upanishads accompanied by Gaudapada's Karika. This lecture covers Mantra 1.