The «Heterenomy» of Kantian Will. A Comparison with Thomas Aquinas

Abstract

The Kantian ideal is to establish a rational foundation of morality, accessible to everybody, independently of each own religiuos beliefs or even in absence of these beliefs. However, the Kantian practical reason does not ultimately fulfill this ideal, because the subject must have rational faith in the existence of God in order to promote its object, the supreme good, that is, the union between morality and its proportional happiness. God is the cause of this harmony in the afterlife. The cause of this reason’s «heteronomy» is precisely Kant’s foundation of the autonomy of will. At the bottom of this problem lies the question of how moral law influences man’s desire in order that his reason could be really practical. Thomas Aquinas has this problem resolved thanks to his metaphysical anthropology. According to Thomas, the origin of human acts resides in the agent, who moves himself for an end not only known, but also desired, being thus the owner of his actions with a kind of «personal autonomy»