Aristotle, Hume, and Kant on Reason, Desire, and Morality

Desires, Feelings, and Reason: Hume vs. Aristotle

David Hume is one of the most significant philosophers of the 18th century. Hume is skeptical about moral truths, and he argues that ethics comes from feelings, not reason. Hume maintains that moral judgments are founded on sentiment — feelings of disapproval or approval — rather than reason. He further asserts that feelings and desires are independent of reason. According to Hume, reason handles the connection of concepts or matters of fact. An examination of common moral evils discloses neither links of concepts nor matters of fact, but only sentiment (Hume 16).

To confirm that desires and feelings are not in accordance with reason, and that they are not controlled or directed by reason, Hume employs three examples: murder, ingratitude, and incest. Hume considers why incest among humans is not right while the same act in animals is considered acceptable. He argues that there is no disparity in the connection of concepts or in the fundamental facts — the only disparity is that human beings disapprove of incest among themselves but not in animals. With respect to murder, Hume thinks that the wrongness of murder is not found in any objective fact or reasoning about links of ideas (White 31). Regarding the crime of ingratitude, the wrong is not found in links of concepts, nor is it an observable fact. Rather, the crime of ingratitude is found in the ungrateful person's mind: it is a feeling of indifference or ill-will. Hume therefore concludes that morality is determined by feelings and desires, not reasoning. Desires and feelings can differentiate between vice and virtue, while reason cannot (White 31).

By contrast, Aristotle holds that desires and feelings are under the control of reason. According to Aristotle, a person's desires and feelings listen to reason (Aristotle 18). Reason is drawn upon as human beings grasp the condition they are in, and as a result, feelings and desires rely on situational understanding. The attitude people take toward a given condition arises from the comprehension they bring to it and their judgment of the values at stake. A person's desires and feelings are dependent on reason and intimately linked to its exercise. People's feelings are not arbitrary; they are determined through the significance that people assign to aspects of themselves and the world. For instance, if a person judges the consumption of snake to be disgusting, then that person will feel repelled by a burger when he or she learns that snake is one of its ingredients.

According to Aristotle, every action holds a final cause — the good at which the activity aims. He argues that the absence of an infinite regress of merely extrinsic goods gives way to a greatest good toward which all human actions ultimately aim (Aristotle 18). The ultimate end of human actions is happiness. The human "good" must essentially entail the whole proper function of human life, and this must be a soul activity that expresses genuine excellence or virtue. Aristotle argues that when people choose to undertake an activity, they do so with a view to some end. A person who performs a virtuous action, however, does not do it virtuously unless he chooses it for its own sake. Actions are carried out for the sake of other things, and the actions people undertake are not themselves the ends with a view to which they undertake them.

Aristotle states that whereas contemplation does not aim at any end beyond itself, fine actions aim at some end and are not desirable merely for their own sake in isolation. Doing good and noble actions is desirable in itself — nothing is sought beyond the activity. What makes a painful action pleasant is the fineness of the end the virtuous person aims at (Miller 256). The virtuous person acts with pleasure because he acts for the sake of the fine. Fine actions are those whose benefit is noble and admirable, and as a result, someone who does not enjoy virtuous action is not truly good.

Enjoying Fine Actions: Aristotle and Kant on Virtue and Good Will

Aristotle's conceptualization of morality, however, brought to light some of the controversies that moral philosophy has faced since his time. Rather than describing a universal morality, Aristotle offered a more subjective conceptualization grounded in virtuous character traits. Following Aristotle, a debate emerged over whether rationality or emotion serves as the proper basis of morality. Immanuel Kant came down firmly against Aristotle's position. While Kant believes that reason should be the foundation of morality, he regarded emotion as a hindrance to truly moral conduct (Kant 16).

With respect to fine actions, Kant argues that only the will of a person can be considered unconditionally good — a good will is intrinsically good. A good will is good not because of what it accomplishes or because of its fitness to attain some proposed end. Kant maintains that the end cannot justify the means, and neither means nor ends can substitute for the will. Good will is necessarily good, and fine actions are performed not for the sake of what is fine, but out of good will. An obligatory action has moral worth only when it is carried out from good will. Kant's idea of good is more compelling than Aristotle's because Kant addresses goodness in a universal manner through the categorical imperatives. Kant suggests that to do an action from duty is to do it out of respect for moral law, as opposed to doing it from inclination or from any preference for expected outcomes (Tamborini 4). Some actions may conform to duty while being done from emotions of sympathy and love — such actions are fine and amiable and deserve praise, but they lack moral worth in Kant's sense and do not deserve moral esteem.

Like Aristotle, Kant holds that reason is, and should be, the foundation of morality (Miller 256). Emotions, according to Kant, hinder true moral behavior, and for one to be truly moral, the burden of morality must rest on cool, calculating reason rather than instincts and interests. Kant maintains that good will is derived from reason, and he stresses the importance of grounding morality in a priori standards.

Hume, on the contrary, claims that there is no morality without feelings. He believes that emotion is a fundamental motivator for moral conduct and that emotions are the most important form of experience. Concepts are reflections of impressions — they are simply symbolic representations of the real environment (Hume 68).

Kant and Hume differ on how moral standards are derived. Kant explains how moral standards are normatively established, arguing that moral principles are those agreed upon by all persons who use rationality as their foundation (Tamborini 4). He maintained that moral principles cannot be discovered by examining people's behavior; rather, they are derived purely through reason.

Moral Distinctions and Their Origin: Hume vs. Kant

Hume's approach to moral principles differs markedly. Hume focuses on discovering moral standards through a process of scientific observation and grounds his moral philosophy in empiricism. In his view, moral principles are established through observing people's conduct. Hume's emphasis on empiricism initiated the social-scientific study of morality, moving the inquiry from the domain of pure philosophy toward the realm of science (Tamborini 4).

Kant's view on the discovery of moral principles is ultimately more convincing. It is difficult to discover a standard that commands all rational beings with unconditional force through the empirical method alone (Tamborini 4). The a priori method is more practical given that moral principles are categorical in nature.

Kant holds that certain forms of action — such as theft, lying, and murder — are absolutely prohibited even in situations where such actions would lead to happiness. The wrongness or rightness of activities does not rely on their consequences, but rather on the duty they fulfill. According to Kant, Categorical Imperatives determine moral duties. An imperative is a command, and categorical imperatives command unconditionally. The categorical imperative is one of the foundational pillars of Kantian ethics. Kant maintains that imperatives or rules can be either categorical or hypothetical. Categorical rules are binding; they reflect what logic would drive the will of all rational beings to accept. Rules against murder or lying are laws that one can always discharge — things one can refrain from doing. Such rules are called perfect duties, which must not conflict with one another. Perfect duties are binding on all rational beings at all times. Kant derives categorical imperatives through the formulas of universal law, humanity, and the kingdom of ends. When these three formulations are followed, perfect duties are realized.