Fulvio Di Blasi discusses the free will’s dependence upon the faculty of reason in “Slaves of Reason?”
Thomas Aquinas explains that we have free will because our judgment of reason is never necessitated to just one course of action. Reason, by definition, compares and analyzes possibilities. Therefore, it is intrinsic to how reason knows its object that the former is free and undetermined.
It might appear bizarre that Aquinas proves that we have free will by focusing on the object of reason rather than that of the will. The reason he relies on this methodology is that the will is nothing other than the inclination towards the object that is known to be good by reason. Therefore, whenever reason selects the best course of action, the will is necessitated to follow it.
It is a common mistake to assume that, based on the above analysis of the will, the latter is not free. The nature of the object of the will is determined by the nature of the cognitive power that provides it, which, as we have said, is reason. Therefore, since reason is by nature free, so too is the will. In other words, since reason is not determined to judge that one option is better than the others, neither is the will determined to choose one option instead of the others.
DR. FULVIO DI BLASI IS AN INTERNATIONALLY RENOWNED SCHOLAR IN THE FIELD OF MORAL PHILOSOPHY, NATURAL LAW THEORY, AND THOMISTIC PHILOSOPHY. HE IS FOUNDER AND PRESIDENT OF THE THOMAS INTERNATIONAL PROJECT, PRESIDENT OF THE THOMAS INTERNATIONAL ASSOCIATION IN ITALY, AND DIRECTOR OF THE THOMAS INTERNATIONAL CENTER IN RALEIGH, NC.