Identifying the roots of the Tibetan Practice of Buddhist Philosophy in one seminal text When, and why, did Tibetans first begin to practice Buddhist philosophy? What was the impetus behind this pivotal cultural development, now so inextricable from Tibetan identity? Dominic Sur illuminates this defining historical moment with his examination of the emergence of early dzokchen philosophy, a distinctive style of Buddhist thought and practice characteristic of Tibet. Sur offers a groundbreaking analysis of the form and content of Entering the Way of the Great Vehicle-Tibetan Buddhism's first polemical apology, in which the great eleventh-century translator and polymath Rongzom ChOEkyi Zangpo presented a creative and masterful philosophical defense of authenticity and authority in Tibetan dzokchen-and documents the historical context and ideas that informed Rongzom's foundational work. This is the authoritative intellectual history of the early Tibetan practice of Buddhist philosophy and the development of dzokchen, one that establishes Sur's status as a leading voice in the field.