 Throughout his enormously active life as a philosopher and theologian, Arnauld was above all concerned to defend the doctrine that human beings, after the fall of Adam, can perform meritorious actions, but only if the actions are the result of a supernatural grâce efficace par elle-même. Arnauld claimed to find this doctrine in the writings of both Augustine and Aquinas and he defended Jansen’s version of it against the charge of heresy, even though Jansen’s version was significantly different from that espoused by Arnauld himself. But Arnauld, like Augustine, Aquinas, and Jansen, also held that actions are meritorious only if they are free. For this reason, Arnauld is sometimes said to be a “compatibilist.” For example, Robert Sleigh says, “It is worth noting that Leibniz and Arnauld both ascribed compatibilism to St. Thomas and that both accepted compatibilism as well” (Sleigh 1990, 29).