Moral Philosophy According to Immanuel Kant

Kantian Ethics in a Nutshell

Portrait of Immanuel Kant
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Immanuel Kant (1724-1804) is generally considered to be one of the most profound and original philosophers who ever lived. He is equally well known for his metaphysics–the subject of his "Critique of Pure Reason"—and for the moral philosophy set out in his "Groundwork to the Metaphysics of Morals" and "Critique of Practical Reason" (although "Groundwork" is the far easier of the two to understand).

A Problem for the Enlightenment

To understand Kant’s moral philosophy, it's crucial to be familiar with the issues that he, and other thinkers of his time, were dealing with. From the earliest recorded history, people’s moral beliefs and practices were grounded in religion. Scriptures, such as the bible and the Quran, laid out moral rules that believers thought to be handed down from God: Don’t kill. Don’t steal. Don’t commit adultery, and so on. The fact that these rules supposedly came from a divine source of wisdom gave them their authority. They were not simply somebody’s arbitrary opinion, they were God's opinion, and as such, they offered humankind an objectively valid code of conduct.

Moreover, everyone had an incentive to obey these codes. If you “walked in the ways of the Lord,” you would be rewarded, either in this life or the next. If you violated the commandments, you'd be punished. As a result, any sensible person brought up in such a faith would abide by the moral rules their religion taught.

With the scientific revolution of the 16th and 17th centuries that led to the great cultural movement known as the Enlightenment, these previously accepted religious doctrines were increasingly challenged as faith in God, scripture, and organized religion began to decline among the intelligentsia—that is, the educated elite. Nietzsche famously described this shift away from organized religion as “the death of God.”

This new way of thinking created a problem for moral philosophers: If religion wasn’t the foundation that gave moral beliefs their validity, what other foundation could there be? If there is no God—and therefore no guarantee of cosmic justice ensuring that the good guys will be rewarded and the bad guys will be punished—why should anyone bother trying to be good? Scottish moral philosopher Alisdair MacIntrye called this “the Enlightenment problem.” The solution moral philosophers needed to come up with was a secular (non-religious) determination of what morality was and why we should strive to be moral.

Three Responses to the Enlightenment Problem

  • Social Contract Theory—One answer to the Enlightenment Problem was pioneered by English philosopher Thomas Hobbes (1588-1679) who argued that morality was essentially a set of rules that human beings agreed upon amongst themselves in order to make living with one another possible. If we didn’t have these rules—many of which took the form of laws enforced by the government—life would be absolutely horrific for everyone.
  • Utilitarianism—Utilitarianism, another attempt to give morality a non-religious foundation, was pioneered by thinkers including David Hume (1711-1776) and Jeremy Bentham (1748-1842). Utilitarianism holds that pleasure and happiness have intrinsic value. They are what we all want and are the ultimate goals that all our actions aim toward. Something is good if it promotes happiness, and it is bad if it produces suffering. Our basic duty is to try to do things that add to the amount of happiness and/or reduce the amount of misery in the world. 
  • Kantian Ethics—Kant had no time for Utilitarianism. He believed in placing the emphasis on happiness the theory completely misunderstood the true nature of morality. In his view, the basis for our sense of what is good or bad, right or wrong, is our awareness that human beings are free, rational agents who should be given the respect appropriate to such beings—but what exactly does that entail?

The Problem With Utilitarianism

In Kant’s view, the basic problem with utilitarianism is that it judges actions by their consequences. If your action makes people happy, it’s good; if it does the reverse, it’s bad. But is this actually contrary to what we might call moral common sense? Consider this question: Who is the better person, the millionaire who gives $1,000 to charity in order to score points with his Twitter following or the minimum-wage worker who donates a day’s pay to charity because she thinks it's her duty to help the needy?

If consequences are all that matter, then the millionaire’s action is technically the "better" one. But that’s not how the majority of people would see the situation. Most of us judge actions more for their motivation than by their consequences. The reason is obvious: the consequences of our actions are often out of our control, just as the ball is out of the pitcher’s control once it's left his hand. I could save a life at the risk of my own, and the person I save could turn out to be a serial killer. Or I could accidentally kill someone in the course of robbing them, and in doing so might unwittingly save the world from a terrible tyrant.

The Good Will

Kant’s "Groundwork" opens with the line: “The only thing that is unconditionally good is a good will.” Kant’s argument for this belief is quite plausible. Consider anything you think of in terms of being "good"—health, wealth, beauty, intelligence, and so on. For each of these things, you can also likely imagine a situation in which this so-called good thing is not good after all. For instance, a person can be corrupted by their wealth. The robust health of a bully makes it easier for him to abuse his victims. A person’s beauty may lead her to become vain and fail to develop emotional maturity. Even happiness is not good if it is the happiness of a sadist torturing unwilling victims.

By contrast, goodwill, says Kant, is always good—in all circumstances. What, exactly, does Kant mean by goodwill? The answer is fairly simple. A person acts out of goodwill when they do what they do because they think it is their duty—when they act from a sense of moral obligation.

Duty vs. Inclination

Obviously, we don’t perform every little action from a sense of obligation. Much of the time, we're simply following our inclinations—or acting out of self-interest. There's nothing intrinsically wrong with that, however, no one deserves credit for pursuing their own interests. It comes naturally to us, just as it comes naturally to every animal.

What is remarkable about human beings, though, is that we can, and sometimes do, perform an action from purely moral motives—for example, when a soldier throws himself on a grenade, sacrificing his own life to save the lives of others. Or less dramatically, I pay back a friendly loan as promised even though payday isn't for another week and doing so will leave me temporarily short of cash.

In Kant’s view, when a person freely chooses to do the right thing simply because it is the right thing to do, their action adds value to the world and lights it up, so to speak, with a brief glow of moral goodness.

Knowing Your Duty

Saying that people should do their duty from a sense of duty is easy—but how are we supposed to know what our duty is? Sometimes we may find ourselves facing moral dilemmas in which it's not obvious which course of action is morally correct.

According to Kant, however, in most situations are duty is obvious. If we're uncertain, we can work out the answer by reflecting on a general principle that Kant calls the “Categorical Imperative.” This, he claims, is the fundamental principle of morality and all other rules and precepts can be deduced from it.

Kant offers several different versions of this categorical imperative. One runs as follows: “Act only on that maxim that you can will as a universal law.”

What this means, basically, is that we should only ask ourselves, How would it be if everyone acted the way I’m acting? Could I sincerely and consistently wish for a world in which everyone behaved this way? According to Kant, if our action is morally wrong, the answers to those questions would be no. For instance, suppose I’m thinking of breaking a promise. Could I wish for a world in which everyone broke their promises when keeping them was inconvenient? Kant argues that I could not want this, not least because in such a world no one would make promises since everyone would know that a promise meant nothing.

The Ends Principle

Another version of the Categorical Imperative that Kant offers states that one should “always treat people as ends in themselves, never merely as a means to one’s own ends." This is commonly referred to as the “ends principle.” While similar in a way to the Golden Rule: "Do unto others as you would have them do unto you," it puts the onus for following the rule on humankind rather than accepting the strictures of divine influence.

The key to Kant’s belief regarding what makes humans moral beings is the fact that we are free and rational creatures. To treat someone as a means to your own ends or purposes is to not respect this fact about them. For instance, if I get you to agree to do something by making a false promise, I am manipulating you. Your decision to help me is based on false information (the idea that I’m going to keep my promise). In this way, I have undermined your rationality. This is even more obvious if I steal from you or kidnap you in order to claim a ransom.

Treating someone as an end, by contrast, involves always respecting the fact that they are capable of free rational choices which may be different from the choices you wish them to make. So if I want you to do something, the only moral course of action is to explain the situation, explain what I want, and let you make your own decision.

Kant’s Concept of Enlightenment

In his famous essay “What is Enlightenment?” Kant defines the principle as “man’s emancipation from his self-imposed immaturity.” What does this mean, and what does it have to do with his ethics?

The answers go back to the problem of religion no longer providing a satisfactory foundation for morality. What Kant calls humanity’s “immaturity” is the period when people did not truly think for themselves, and instead, typically accepted moral rules handed down to them by religion, tradition, or by authorities such as the church, overlord, or king. This loss of faith in previously recognized authority was viewed by many as a spiritual crisis for Western civilization. If “God is dead, how do we know what is true and what is right?"

Kant’s answer was that people simply had to work those things out for themselves. It wasn't something to lament, but ultimately, something to celebrate. For Kant, morality was not a matter of subjective whim set forth in the name of god or religion or law based on the principles ordained by the earthly spokespeople of those gods. Kant believed that “the moral law”—the categorical imperative and everything it implies—was something that could only be discovered through reason. It was not something imposed on us from without. Instead, it's a law that we, as rational beings, must impose on ourselves. This is why some of our deepest feelings are reflected in our reverence for the moral law, and why, when we act as we do out of respect for it—in other words, from a sense of duty—we fulfill ourselves as rational beings.

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Westacott, Emrys. "Moral Philosophy According to Immanuel Kant." ThoughtCo, Apr. 5, 2023, Westacott, Emrys. (2023, April 5). Moral Philosophy According to Immanuel Kant. Retrieved from Westacott, Emrys. "Moral Philosophy According to Immanuel Kant." ThoughtCo. (accessed May 30, 2023).