What Is the Main Rule of Life Taught by Kant’s Philosophy?

Kant's philosophical viewpoint encourages us to live with a purpose and to strive for self-improvement constantly.

Apr 15, 2024By Viktoriya Sus, MA Philosophy

kant philosophy rule life


What is the main rule of life? Many people may believe that they are “right,” but few have had as much influence on ethics as German philosopher Immanuel Kant. His deontological philosophy provides a lesson for how we ought to live our lives: each individual must strive for universal morality.


Through understanding Kant’s ethics, we also learn how to make better decisions, live more ethically, and be better citizens of the world. In other words, his teachings provide an invaluable tool for us to be the best version of ourselves.


The Question at Hand

immanuel kant german philosophy
Immanuel Kant. Source: Wikipedia


Kant’s philosophy assumes that all people have certain inherent worth. This worth would include things such as respect and honor among one another. He believed that we ought to treat others the way we’d like to be treated—similar to what most have known as the “Golden Rule.”


His most well-known ethical principle assumed we should aspire towards universal moral laws consistent across different cultures, societies, and time periods. Because of this assumption, this implies that even if an individual disagrees with the moral law, they still have to abide by it because that is out of respect for universal morality. So, what is the main rule of life?

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Who Was Immanuel Kant?

doerstling kant friends painting
Kant and Friends with Table, Emil Doerstling, 1892-93, Source: Wikimedia Commons


Immanuel Kant was a brilliant German philosopher who lived from 1724 to 1804. Born in Königsberg (now Kaliningrad, Russia), he spent his entire life in the city, with a strict routine that earned him the nickname “the clockwork man.”


He is considered one of the greatest thinkers in Western philosophy and is especially renowned for his work on epistemology and ethics. His contributions fundamentally shaped the Enlightenment era and continue to influence contemporary philosophy.


Kant began life as a poor but hardworking saddler’s son, attending the local university where he excelled academically. A decade later, following an intrepid pursuit of knowledge and tireless research, he went on to become a professor of logic and metaphysics at the same institution.


Much of Kant’s most important work appears in his masterpiece Critique of Pure Reason, published in 1781. Here, he offers a monumental treatise on understanding human knowledge and how we see reality. He held that our experience is structured or organized by certain mental concepts or frameworks called “categories,” which shape our understanding of the world.


Notably, Kant separated phenomena (things as they appear) from noumena (things as they are), stressing that we can never fully know reality as it is beyond our subjective perceptual construct.


Alongside epistemology, Kant explored moral philosophy with his influential work called Groundwork of the Metaphysics of Morals. There, he offered an ethical system beginning with reason called the categorical imperative. It states that individuals should act only in ways that could be universally applied without contradiction.


Most importantly, Kant’s theories were enormously influential within philosophy and across various other disciplines, such as political science and psychology. From there, many subsequent philosophers built upon his ideas or historically critiqued them rigorously.


What is Kant’s Moral Philosophy?

lucas cranach fountain youth painting
The Fountain of Youth, Lucas Cranach the Elder, 1546, Source: Wikimedia Commons


At first glance, Kant’s moral philosophy seems odd and difficult to follow. He believed that something could only be considered truly good if it applies everywhere, making lying a bad act for the person doing it and everyone else involved in this falsity.


Kant’s moral philosophy is built upon the idea of imperative and action according to the categorical. The categorical imperative states that one should act in such a way that everyone can agree on and universally approve as morally right. In other words, it claims that to do the right thing simply because it is the right thing to do—that is morality.


This means that motivation for morality would no longer be based on self-interest but rather a positive impulse to spread goodness amongst all people and hence respect them as moral beings. Correspondingly, Kant’s moral philosophy seeks to ensure ethical decisions are made consistently across different contexts because this would mean a world of justice.


So, as per Kant’s categorical principle imperatives, lying is evil and must never be tolerated regardless of the number of victims or when they are done to them. These universal principles apply to any situation; everyone should live by them.


jacques louis david death socrates painting
The Death of Socrates, Jacques Louis David, 1787, Source: The Metropolitan Museum of Art


Some philosophical ideas have gone through their fair share of criticisms, questioning whatever acceptance was for them in the first place; others have stood the test of time.


Still, the most important rule Kant states is that treating humans as ends in themselves and not as a means to an end is most important. Another fact he stated about himself is that consciousness, according to him, is sacred, and thus, he used the term when he meant rationality.


On current knowledge, we are the only case of extraordinary intelligent self-organization in the Universe, meaning we are solely capable of making choices, considering options, and evaluating the ethical implications of our actions.


Hence, we should approach this matter with seriousness wherever foundations for moral judgment must be made on rationality and safeguarding conscious decision-making. What exactly should we do? See the rule above.


Critical Components of a Good Life

georges seurat sunday on la grande painting
A Sunday on La Grande Jatte, Georges Seurat, 1884-86, Source: Art Institute Chicago


Kant believed a good life consists of four essential elements: self-development, morality, bravery, and rationality. These elements are all interrelated—morality and bravery rely on self-development for their existence, which in turn relies on rationality.


For Kant, self-development involves a process of achieving the highest degree of client autonomy possible. He thought creativity and exercising one’s judgment were important constituents of self-development.


Kant also believed in the importance of morality as an absolute duty—something we must do. He saw moral decisions as things that cannot be made based on one’s interests. Instead, they should always be judged by universal principles.


Lastly, Kant talked about bravery as crucial to a good life. By this, he meant endorsing activeness under challenging situations instead of fear or selfishness (what we call cowardliness nowadays)—that is what he called the “courage to be oneself.”


Kant emphasized rationality deeply, considering it essential for moral decision-making and self-development. He said human beings need to use their reason to understand and evaluate things around them and to interact with other people ethically.


Kant explains the concept of a “good life” in his famous book Critique of Pure Reason. To live a good life, he says, we need to pursue what we enjoy, stay active, and have a clear goal in mind. Also, we ought to display kindness to others, avoiding inflicting harm on them at all costs. If these things keep us abreast, we will all lead good lives.


A fulfilling life obviously entails both pleasure and significance. If we don’t enjoy doing things just because they are enjoyable, there’s no point in doing anything. We can only find significance if we look for activities and experiences congruent with our values and priorities.


Self-Development as a Key Rule of Life

george cotman dame school painting
The Dame School, Frederick George Cotman, 1887, Source: WikiArt


For most Enlightenment philosophers, utilitarianism was the preferred philosophy to live a good life. It is the process of maximizing happiness and minimizing suffering. Even today, this is still looked upon as quite aligned with reality. However, Kant had a bitter criticism of these philosophies. He encouraged personal growth by saying that one can only improve the world around them by improving themselves first.


In many cases, knowing if the person deserves happiness or suffering is impossible, thanks to the impossibility of knowing their real intentions and goals. If it’s worth making someone happy, then you don’t know what exactly would be needed for this purpose. You don’t know the other person’s feelings, values, or expectations. You don’t know how your actions would affect him.


Moreover, the definition of happiness and suffering is ambiguous. Divorce may induce unbearable pain at the time, but in a year, one may see it as the best thing that has happened. Thus, the inclination towards most rationally to improve the world is to improve ourselves because we can be sure only of our own being.


According to Kant, the development of self means adhering to moral principles known as categorical imperatives, which is a duty that everyone should perform. He believed that not fulfilling this duty causes negative consequences in one’s own life rather than in the afterlife.


By abiding by moral principles, not only does an individual’s quality of life improve, but it also improves the lives of people around him. On the contrary, violating these ethics engenders unnecessary pain in oneself and others.


According to Kant’s rule, telling the truth to oneself may lead to a direction where you are telling the truth to others, thus starting a chain reaction of honesty, giving rise to positive changes in people’s lives. It just needs more individuals to follow its rules for its power to make a bigger impact toward positive change in the world.


How Can Kant’s Philosophy Affect Us?

jacopo tintoretto allegory fortune painting
Allegory of the Fortune, Jacopo Tintoretto, 1544-45, Source: Wikimedia Commons


Deeply scratching into Kant’s philosophy, you will find many contradictions. But his first ideas are so powerful that they have turned the world upside down. Kant believed that everyone must be respected and treated with dignity. This thought changed people about themselves—everyone is an end in itself.


His moral philosophy also makes us think about where we move in our actions, to never do something that can damage someone else, even if there is a good cause. For example, lying to receive more: Kant’s moral philosophy would tell us it is bad to lie just to get money because doing so harms the person being lied to.


Nevertheless, what exactly we do is not so important; the purpose of these actions is important. Until you find the right target, you won’t find anything worthwhile. Kant was not exactly a nerd who was obsessed with routine. In his youth, he liked to have fun too. He slept late with friends, drinking red wine and playing cards. He woke up late, overindulged, and threw big parties.


Only at 40 did Kant give this up and start making his famous routine. According to him, he understood the moral consequences of his deeds and decided he would no longer allow himself to squander precious time and strength.


This word was “to develop character.” That is, to build a life, trying to squeeze your potential performer. Developing character, he believed most people would fail to achieve this goal until adulthood.


In youth, people are too seduced by various pleasures; they are thrown from side to side – enthusiasm to despair and back. We worry too much about the accumulation of funds and don’t see what goals drive us.


To develop character, one must learn how to control his actions and himself. Only some people can achieve this goal-making sense, but Kant believed this is what everyone should try for. It’s the only thing worth shooting for.

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By Viktoriya SusMA PhilosophyViktoriya is a writer from L’viv, Ukraine. She has knowledge about the main thinkers. In her free time, she loves to read books on philosophy and analyze whether ancient philosophical thought is relevant today. Besides writing, she loves traveling, learning new languages, and visiting museums.