Kant believes natural law is written in the human heart. For him, the highest good can be understood as happiness, which is distributed in exact proportion to morality (First Critique). Therefore, in a sense, the highest good can be defined as the combination of happiness and virtue. However, this definition is not clearly held in all Kantian writings, something which arises an ambiguity that has been the object of ongoing research. For instance, in the Second Critique, Kant also speaks of the supreme good as a consummated or transcended good. A widespread way to approach the issue has been claiming …

For Aquinas, everything is regulated by eternal law or God’s creation order (I-II, Q.91, a.3), so it is no surprise that he understands natural law as participation of the eternal law, where natural law is of a general and teleological character (See I-II, Q.91, a.2). In Aquinas’s vision, natural law is linked with divine reason rather than with the will of God, as theologians such as Calvin would suggest. This opens the door for considering Aquinas’s notion of natural law to be expansive in the sense that natural law is associated with human’s capacity to reason and producing reflection. When …