Similarities between Aquinas and Aristotle


I: Both hold that humans have a function and that virtue is necessary for its fulfillment.


II: Both hold that certain sorts of actions are intrinsically wrong and that we can know that they are by intellectual apprehension and reason.


III: Both hold that things have natures, that their natures determine what is good for them and what is bad for them, and that wickedness is contrary to human nature.

Differences between Aquinas and Aristotle


I: Aquinas thinks humans are ordered to a supernatural end the achievement of which requires the supernatural virtues of faith, hope and love.


II: Aquinas believes that the natures of all things are rooted in God [all things are like God in some way] and thus that the ground for all necessary truths is the divine nature.


III: Aquinas believes that the natural law, when understood strictly as the moral law, is not simply known by reason and based on the natures of things, but is also based on Godís nature and is enjoined by God.


IV: Aquinas very explicitly roots moral principles in the intrinsic value of things.


V: Aquinas expressly formulates one ultimate moral precept and provides for specificatory principles that will allow one to clearly apply that precept to particular moral questions