The Precious Treasury of Philosophical Systems discusses the philosophical tenets of the entire spectrum of Buddhist teachings-Hinayana, Mahayana, Vajrayana, and Dzogchen. This series consists of the volumes written by Longchen Rabjam that that, as a group, have come to be known as The seven Treasuries. Although, Longchenpa did not intend them to be series, scholars traditionally treat them as such because of their interrelated themes.