Paige Ellis
Mr. Stripling
Philosophy 201
27 April 2018
Kant’s Moral Theory vs. Aquinas’s Theory of Natural Law
In the work of Immanuel Kant and St. Thomas Aquinas, they address their theories on morality. In Kant’s “The Grounding for the Metaphysics of Morals,” he explains that science is learned empirically or a priori. Generally, he is trying to explain how an individual can be moral. In Aquinas’s “Treatise on Law: Summa Theologica,” he attempts to explain the purpose of the entire universe and the role that everything in the universe. In this essay, I will compare Kant’s moral theory and Aquinas’s theory of natural law and determine which theory is better and more rational. In the first body paragraph, Kant’s categorical imperative and autonomy will be the main focus. Then in the second body paragraph, the focus will shift to Aquinas’s first principle of practical reason and our natural inclinations. The next two paragraphs will have explanations of the similarities and differences of the moral theory and the theory of natural law. Finally, I will determine if Kant’s view of morality or Aquinas’s view of morality is more rational.
In Kant’s “The Grounding for the Metaphysics of Morals,” Kant argued that the supreme principle of morality is the categorical imperative. Kant defined the categorical imperative as a command that is an essential rule that an individual must follow, regardless of his or her desires. They are moral obligations that are derived from pure reason. Categorical imperatives apply to everyone because these commands are unconditional as morality applies to all human beings. The first formulation of the categorical imperative is, “Act only on that maxim through which you can at the same time will that it should become a universal law of nature”. Generally, this statement means that a person should not do an action unless that action could be a universal law. For instance, a person should not borrow money that they do not intend to pay back because then everyone would be able to make promises that they would not be able to keep. To universalize this law would be a contradiction because no one would be able to trust anyone since everyone would be able to lie. According to the categorical imperative, this makes lying not allowed and immoral as a person cannot make exceptions to the universal law for themselves. Kant states that the second formulation of the categorical imperative is, “Act so that you treat humanity, whether in your own person or in that of another, always an end and never as a mean means”. This quote explains the idea that a person should not use another person as mere means. To use someone as a mere means is immoral because we are end-in-ourselves. It is acceptable for us to use objects for our own benefit because they are not end-in-themselves. However, humans are not objects and they exist for their own end. Due to our autonomy, individuals deserve to not be treated as mere means. Since humans are rational beings that have the freedom to make our own decisions and ends based on wills, we have an absolute moral worth. If one person treats another person is treated a mere means to accomplish their goals, then Kant’s second formulation is violated. Kant believes that the categorical imperative will lead us to moral truth that is same for everyone and available to everyone.
In Aquinas’s “Treatise on Law: Summa Theologica,” he states that natural law is the specifically human way of participating in eternal law, which natural law is derived from. The theory of natural law is rooted in human nature and therefore is universal. Aquinas believes that the theory of natural law is based around the idea that God gave humans the tools they need in order to do good and be good. God wants humans to do good things with their lives and this is reflected in the first principle of practical reason. This principle states that a human needs to do good and avoid evil. Aquinas believes that the first principle is self-evident to us because it is based on our nature and doesn't need to be questions. However, although God gave us the tools to be good, humans still need to use their reason and conscience in order to make good decisions. In Question 94, Article 2, Aquinas states that the first thing that we are apprehended towards is the good because people act to meet their ends. However, a person should never act for the end they are trying to obtain. This explains that the first principle of practical reason is “good is pursued and evil is to be avoided” because we are naturally drawn to the good in the world. We are inclined to do good because our natural inclinations reveal what the most fundamental goods are. Our natural inclinations include the following: the inclination to good in accordance with nature, the inclination to things that pertain to him and the inclination to good in accordance to the nature of his reasons. It is important to act on our inclinations; however, not all inclinations are moral. We must acknowledge the purpose of the inclination and then assess it using our reason. If the inclination is not moral then we must not act on it. The theory of natural law guides individuals to do good and avoid evil through their natural inclinations.
A main difference between Kant’s moral theory and Aquinas’s natural law is that Aquinas believes that God is the root of human nature. The natural law would have arisen if it wasn't for the existence of God and his connection with human beings. Aquinas states that since God created human beings, we have moral sensibilities. Human beings only have morality because we were created by God. Kant argued that reason was behind morality, not religion. This was contrary to Aquinas’s belief because Kant believed that every individual could reach moral truth and there was no need for the assistance of God. Since there are a vast amount of religions, if morality was based off of religion then there would be discrepancies among morality. A main similarity of Kant’s moral theory and Aquinas’s natural law is that they both emphasized the importance of morality. Despite whether being immoral would affect you religiously or not, it still had a negative impact. To Kant, a person must act as if their actions were a universal law while to Aquinas, a person must follow their good natural inclinations in order to follow the first principle of practical reason. Both of these philosophers relate to the common theme of being good, however, their religious views cause them to conflict on some fronts.
I believe that Kant’s moral theory is more rational than Aquinas’s theory of natural law. Although I do agree that everyone should follow their good inclinations, I do not agree with his idea that God is the center of morality. There are too many differences between religions to base morality off of God. Morality is something that every individual should strive to achieve and it should not be equated with something as broad as religion. Overall, I agree with Kant’s first formulation of the categorical imperative because it clearly states that individuals should only perform an action that everyone else could perform. It is not right to make exceptions for yourself and not apply those exceptions to others. Kant’s theory is more inclusive, clear, and rational than Aquinas’s theory.
Kant’s moral theory and Aquinas’s theory of natural law explains their views on morality. Although they both stress the idea that every person should be moral, their difference of religion divides them. I believed that Kant’s theory was more rational since I resonated more with the idea that religion did not play as significant of a role and the level of clarity he explained his arguments at. In this essay, I have compared Kant’s moral theory and Aquinas’s theory of natural law and determined that Kant’s moral theory is more rational.