Book excerpt: This book explains how the authority Thomas Aquinas's theological teachings grew out of the doctrinal controversies surrounding it within the Dominican Order. The adoption and eventual promotion of the teachings of Aquinas by the Order of Preachers ran counter to every other current running through the late thirteenth-century Church; most scholastics, the Dominican Order included, were wary of the his unconventional teachings. Despite this, the Dominican Order was propelled along their solitary via Thomas by conflicts between two groups of magistri: Aquinas's early Dominican followers and their more conservative neo-Augustinian brethren. This debate reached its climax in a series of bitter polemical battles between Hervaeus Natalis, the most prominent of early defenders, and Durandus of St. Pourçain, the last major Dominican thinker to attack Aquinas's teachings openly. Elizabeth Lowe offers a vivid illustration of this major shift in the Dominican intellectual tradition.