Kantian Ethics in a Nutshell: The Moral Philosophy of Immanuel Kant

Portrait of Immanuel Kant
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Immanuel Kant (1724-1804) is, by common consent, 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 his moral philosophy which is set out in his Groundwork to the Metaphysics of Morals and the Critique of Practical Reason. Of these last two works, the Groundwork is by far the easier to understand.

A Problem for the Enlightenment

To understand Kant’s moral philosophy it is crucial first of all to understand the problem that he, like other thinkers of the time, was trying to deal with. From time immemorial, people’s moral beliefs and practices had been based on religion. Scriptures like the bible or the Koran laid out moral rules that were thought to be handed down from God: Don’t kill. Don’t steal. Don’t commit adultery, and so on. The fact that the rules came from God gave them their authority. They were not just somebody’s arbitrary opinion: they gave humanity an objectively valid code of conduct. Moreover, everyone had an incentive to obey them. If you “walked in the ways of the Lord,” you would be rewarded, either in this life or the next. If you violated His commandments, you would be punished. So any sensible person would abide by the moral rules that religion taught.

With the scientific revolution of the 16th and 17th centuries, and the great cultural movement known as the Enlightenment which followed, a problem arose for this way of thinking. Simply put, faith in God, scripture, and organized religion began to decline among the intelligentsia–that is, the educated elite. This is the development that Nietzsche famously described as “the death of God.” And it created a problem for moral philosophy. For if religion wasn’t the foundation that gave our moral beliefs their validity, what other foundation could there be? And if there is no God, and therefore no guarantee of cosmic justice ensuring that the good guys are rewarded and the bad guys are punished, why should anyone bother trying to be good?

The Scottish moral philosopher Alisdair MacIntrye called this “the Enlightenment problem.” The problem is to come up with a secular–that is, a non-religious–account of what morality is and why we should be moral.

Three Responses to the Enlightenment Problem

1. Social Contract Theory

One response was pioneered by the English philosopher Thomas Hobbes (1588-1679). He argued that morality was essentially a set of rules that human beings agreed upon among themselves in order to make living together possible. If we didn’t have these rules, many of which are laws enforced by the government, life would be absolutely horrible for everyone.

2. Utilitarianism

Another attempt give morality a non-religious foundation was pioneered by thinkers like David Hume (1711-1776) and Jeremy Bentham (1748-1742). This theory holds that pleasure and happiness have intrinsic value. They are what we all want and are the ultimate goals that all our actions aim at. 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 or reduce the amount of misery in the world. 

3. Kantian Ethics

Kant had no time for utilitarianism. He thought that in placing the emphasis on happiness it completely misunderstood the 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. Let’s see in closer detail what this means and what it entails.

The Problem With Utilitarianism

The basic problem with utilitarianism, in Kant’s view, 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 this is actually contrary to what we might call moral common sense. Consider this question. Who do you think is the better person, the millionaire who gives $1,000 to charity in order to look good in front of his girlfriend, or the minimum wage worker who donates a day’s pay to charity because he thinks it is is duty to help the needy?

If consequences are all that matter, then the millionaire’s action is better. But that’s not what most people think. Most of us judge actions more by their motives 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 has left his hand. I could save a life at the risk of my own, and the person I save could turn out to be serial killer. Or I could kill someone in the course of stealing from them, and in doing so might accidentally save the world from a terrible tyrant.

The Good Will

The first sentence of Kant’s Groundwork states: “the only thing that is unconditionally good is a good will.” Kant’s argument for this is quite plausible. Consider anything you think of as good: health, wealth, beauty, intelligence, etc. In every case, you can imagine a situation in which this good thing is not good after all. 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 them to become vain and fail to develop their talents. Even happiness is not good if it is the happiness of a sadist torturing his victims.

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

Duty v. Inclination

Obviously, we don’t perform every little act we do out of a sense of obligation. Much of the time we are simply following our inclinations, acting out of self-interest. There is nothing wrong with this. But no-one deserves any credit for pursuing their own interests. That 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. E.g. a soldier throws himself on a grenade, sacrificing his life to save the lives of others. Or less dramatically, I pay back a debt as I promised to do even though this will leave me short of money.

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

Knowing What Your Duty Is

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 where it isn’t obvious which course of action is right.

According to Kant, however, in most situations are duty is obvious. And if we are uncertain we can work it out by reflecting on a general principle that he calls the “Categorical Imperative.” This, he claims, is the fundamental principle of morality. All other rules and precepts can be deduced from it. He 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 we would not b able to do this. 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.” But what does it mean, exactly? 

The key to it is Kant’s belief that what makes us moral beings is the fact that we are free and rational. 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 a famous essay entitled “What is Enlightenment?” Kant defined enlightenment as “man’s emancipation from his self-imposed immaturity.” What does this mean? And what does it have to do with his ethics?

The answer goes back to the issue 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. They typically accepted moral rules handed down to them by religion, by tradition, or by authorities like the Bible, the church, or the king. Many people have lamented the fact that many have lost their faith in these authorities. The result is viewed 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 is that we have to work these things out for ourselves. But this is not something to lament. Ultimately it is something to celebrate. Morality is not a matter of subjective whim. What he calls “the moral law” –the categorical imperative and everything it implies–can be discovered by reason. But it is a law that we, as rational beings, impose on ourselves. It is not imposed on us from without. This is why one of our deepest feelings is reverence for the moral law. And 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.