Aristotle and Immanuel Kant’s Ethical Theories

According to Guyer (2006), ethics is the code of conduct that is widely accepted in the society. The ethical theory of Aristotle states that the good moral of human beings is as a result of the rational reasoning of human beings over what is wrong or right. He argued that whatever is thought to be good has to be applied universally. On the other hand, Immanuel Kant’s ethical theory states that the individual’s ethical morals are the result of the combination of the ability to reason rationally and the presence of the good character traits in an individual.

Murphy, Laczniak, Bowie & Klein (2004) note that despite the different opinions between Aristotle and Kant, there are the similarities in their theories. Kant argues that human beings are very rational, and this guides them in knowing their ethical duties. With this ability to reason, a consistent logical moral behavior is expected of every individual. The same opinion is also seen in Aristotle’s arguments, that the virtues are those traits that enable someone to act according to his or her logical reasoning. Again, Kant says that the consequences of any action are irrelevant to the moral evaluation of any particular action. To him, it is the motivation behind that the particular action that matters. For instance, one may be ethically wrong but with a good motive. Aristotle equally argues that the motive of behavior is what important in determining whether one is wrong or not.

Additionally, Kant believes that the whole immorality comes about as a result of irrationality, even though not every kind of irrationality is the form of immorality. Aristotle also believes that whenever one is irrational, he or she can never have good morals. Finally, both Aristotle and Kant argue that the display of morally unacceptable behaviors from an individual is a sign that the individual is most likely to be very irrational.

Even with such points of agreement, the two scholars have a number of differences. In contrast to Aristotle’s theory, Kant argues that there is nothing in the world that can be said to be good except the good will. While Aristotle’s argument is that there are the things far superior to human beings which can be better than the human beings’ good will. According to Aristotle, a constant practice of rationality can lead the individual to developing good character traits making him a good person. He further says that the moral ethics are not spontaneous actions. On the other hand, Kant argues that the character of the person relies on the observations of basic principles fixed through the rational reasoning of human beings. These moral principles, according to Kant, apply universally to every individual (Colle & Werhane, 2008).

Aristotle Further argues in his theory that happiness is the most precious and final thing for a human being to achieve. According to him, this happiness is a result of morality. He, therefore, emphasizes on the need for every individual to practice happiness. He, thus, implies that the morality in human beings is purposefully driven. Kant, on the other hand, argues that ethics is the result of one’s inner conviction and freedom to choose what is wrong and right but not the final purpose for any human being. He added that morality wholesomely leads to happiness which is the ultimate purpose of each individual. This means that, according to him, happiness is not a pleasure or choice. He argues that ethical moral actions are done for the sake of duty and not just for happiness (Colle & Werhane, 2008).

The two scholars also differ in their explanations of the major reasons why people act. According to Aristotle, the human actions are meant to enable the man to achieve good things. On the other hand, Kant argues that the rational human actions are very vital to the individual’s life since they enable the society to have uniformly guided ethical behaviors among the individuals; hence, a peaceful co-existence. Kant also argues that one should act in the manner that the principles upon which the actions are based and the resulting actions would be fair to each and every one. Their difference on the major reason why people act is further demonstrated by the emphasis from Aristotle that one should act in the manner so as to enable him or her to build a good character which will reward him or her at the highest level of happiness (Colle & Werhane, 2008).

Another point of departure by the two ones is in their views on virtues. Aristotle argues that there are two types of virtues: the moral and intellectual virtues. According to him, intellectual values are partly originated and partly fostered through teaching, while the moral values are the result of the consistent commitment to good habits. On the other hand, Kant argues that virtues are rationally acquired and built upon by observing the universally acceptable actions. Aristotle further argues that virtuous actions are the balance between the extreme sides of something. For instance, he says that being brave is a virtue that is acquired by not being a coward and not being too courageous. While Kant holds that such virtues are as a result of the practice of what is right and what is deemed fair for any other person.

Kant also adds that logic and consistency, therefore, demands that the basic universal rules to be formulated in the way that can enable it to be followed by everyone. He argued that in case one cannot follow the logically made rules, then he is illogical, inconsistent and immoral. To him, this is because such person is not granting the other human beings the same rationality status that he/she claims (the Categorical imperative rule). While Aristotle argues that ethics only tells what a right person is and not setting rules to be followed (the virtuous life), Kant emphasizes what character one should hold in order to be a moral human being (Murphy, Laczniak, Bowie & Klein, 2004).

As far as interrelationship is concerned, Kant argues that any individual should never use any other person for his or her own purposes since every one has got the equal freedom as he or she. On the other hand, Aristotle argues that one only needs to be fair to the rest people because this is what would help him or her to achieve the happiness serving his sole purpose of living. Murphy, Laczniak, Bowie & Klein (2004) further note the argument by Kant that to act ethically is to act with good will. On the other hand, Aristotle only regards the good character traits and not the actions of the individual as a determinant of a good person. The two theorists also differ in that Kant argues that the motive to do something is the source of all moral qualities and not the consequence. On the other hand, Aristotle argues that any action is good only when done with a good motive and by a good person.

However, Guyer (2006) notes that both two theories have their various strengths and weaknesses. He identifies the strengths of Aristotle’s theory as including the laid down fundamental principles that should be practiced for one to be virtuous. These principles are: courage, bravery, justice, and prudence. He further emphasizes that the good character traits should be balanced to enable them to result into the best actions.

Strengths and Weaknesses of Theories

Despite the strengths, Aristotle’s theory also has got its weaknesses. First of all, the virtue ethics by Aristotle does not give specific rules that should guide the behavior of human beings and, therefore, make it difficult to know what constitutes the right or wrong behavior. His theory also focuses much on what kind of person one should be and not what one ought to do or to follow in order to be good. Therefore, the irrational human beings may not know what courses of action to take in some situations. Aristotle’s theory only singles out that the ability to reason is the major function of human beings, and that those who can not be rational can only be unethical (Murphy, Laczniak, Bowie & Klein, 2004).

Aristotle’s fundamental principles of a good character are also not very convincing. For instance, if someone has the courage then it is considered to be a good trait regardless of its impact; since in some cases, this courage may not achieve any good thing for such person. Also according to Aristotle’s argument, a morally bad person with good character traits is better than a morally good person with bad character traits. This is a weakness because whatever is portrayed outside are the actions of any individual and not the character traits.

Just like Aristotle’s theory, Kant’s theory also has got its strengths and weaknesses. The strengths include Kant’s golden rule that states that one should only do to others what he would also wish the others to do for him. This is showing the strength of this theory because it emphasizes the observation and the respect of the morally set ethical rules. It is also a good theory since it does not allow the exceptions in the rule of law. According to his theory, the basic rules apply to everyone regardless of class, gender, and origin. Finally, it is also strong in the sense that it shows the value for every human being by emphasizing that human beings have the rights that have to be respected by others (White & Taft, 2004). 

Despite the strengths, his theory has some weaknesses. These include the suggestion that all human beings can have their abilities imperatively categorized. This theory also disregards the fact that morality can come from other factors such as empathy and compassion. This creates the unbalanced ethical system. The theory also states that the ethical morals can be universally applied. This is not possible since different human beings are influenced differently by particular scenarios. This can, therefore, lead to a conflict of contradictory morals (White & Taft, 2004). 

This theory can also lead to many rules being put in place since they are the result of logical reasoning which has no limit. It is also weak in its view that happiness is the result of leading the moral life and not the intention of leading this kind of life. In addition, the assumption that every individual is rational is also wrong since some lack the capacity. For instance, children may not have the capability to reason over what is right or wrong. Finally, this rule does not consider that some imperatively created rules could be morally insignificant and, therefore, they do not make any difference in the society (White & Taft, 2004). 

In my opinion, therefore, I think that Immanuel Kant’s theory is more correct since it is reasonable enough to say that the ethical standards set in the society today must have been a result of the series of logical thoughts. This is true based on the fact that everyone everywhere is under a sort of institution which has the authority to set laws governing his/her actions. Such laws have undergone some amendments leading to the transformation in the way in which people are expected to act, relate and behave.


In conclusion, the works of these two scholars have greatly contributed to understanding the reasons behind the people’s behavior. Despite the differences in their opinions, Aristotle and Kant have made it clear that the ethical standards of individuals are highly influenced by the individuals’ abilities to reason.