 The authorities most often cited by Arnauld are Augustine and Aquinas in theology, and Augustine, Aquinas, and Descartes in philosophy. Arnauld’s attitude toward these predecessors is complex. From the outset of his published work in philosophy, he claimed that Augustinian themes were present in Descartes. However, in his late work, beginning with On True and False Ideas in 1683, he began to cite Aquinas frequently, as well as Augustine, both in philosophy and theology. Thus, in the 181 folio pages of Ideas, which Arnauld describes as dealing with a purely philosophical topic, he cites Augustine twenty times and Aquinas six times, always claiming that they agree with Descartes and with his own position. Similarly, in the theological part of Réflexions, Arnauld relies heavily on Aquinas’s Christology while arguing that Malebranche’s theodicy leads him into heterodox, if not downright heretical, positions (OA 39:777). Again, in his late work on the problem of human free will and grâce efficace par elle-même, Arnauld took over what he says is the Thomistic position that the will is free when it is a potestas ou facultas ad opposita. And in the controversy with Nicole and others over Nicole’s theory of a grâce générale, Arnauld relied heavily on Aquinas’s account of cognition. So frequently did Arnauld rely on Thomistic formulations in his late work that his friends reproached him for “abandoning Augustine in order to follow Aquinas, thus preferring the disciple to the master” (Règles du bon sens, OA, 10:154). This reproach had to do directly with Arnauld’s rejection of the “Platonism” in Augustine and Jansen. But as shown below, Arnauld, late in his career, also parted company with Augustine and Jansen on the nature of human free will, and with Jansen’s account of the nature of actual grace.