Jeffrey Hopkins continues his groundbreaking exploration of the Jo-nang-ba sect of Tibetan Buddhism with this revelatory translation of one of the seminal texts from that tradition. Whereas Dol-bo-ba's massive Mountain Doctrine authenticates the doctrine of other-emptiness through extensive scriptural citations and elaborate philosophical arguments, Taranatha's more concise work translated here situates the doctrine of other-emptiness within the context of schools of tenets, primarily the famed four schools of Tibetan Buddhism, through comparing the various schools' opinions on the status of the noumenon and phenomena. Also included is a supplementary text by Taranatha which presents the opinions of a prominent fifteenth-century Sakya scholar, Shakya Chok-den, and contrasts them with those of the leading Jo-nang-ba scholar Dol-bo-ba.