Summary of Kant’s Ethics (short version)

Kant gemaelde 3.jpg

(You can find a more detailed summary of Kant’s ethics here.)

Kant’s most basic presupposition regarding ethics was his belief in human freedom. While the natural world operates according to laws of cause and effect, the moral world operates according to self-imposed “laws of freedom.” Here is his basic argument for freedom:

1. Without freedom, morality is not possible.
2. Morality exists, thus
3. Freedom exists.

The first premise is true because, according to Kant, determinism undermines morality. The second premise Kant took as self-evident, and the conclusion follows from the premises. Kant also believed that freedom came from rationality. Here is his argument:

1. Without reason, we would be slaves to our passions (lust, envy, avarice, etc.)
2. If we were slaves to our passions, we would not be free; thus
3. Without reason, we would not be free.

We now have the basis upon which to connect between reason and morality.

1. Without reason, there is no freedom
2. Without freedom, there is no morality, thus
3. Without reason, there is no morality.

Kant believed moral obligation derived from our free, rational nature. But how should we exercise our freedom? What should we choose to do?

Kant’s ethics is the study of our duty. Since we are free, rational beings we can choose between actions, unlike non-human animals who are guided by instinct. Moral actions are actions where reason leads rather than follows. Such actions must take into account other beings that act according to their own conception of the law. Put simply, to be moral we ought to conform our free will to the moral law; that is our duty.

Kant says the only thing that is completely good is a good will—the desire to conform itself to the moral law. But what is the moral law? Kant assumes that there is a moral law, and that there is some rational representation of the moral law that we can understand. And exemplars of laws are laws of nature which are characterized by their  universality. So the moral law, he argued, must be characterized by universality too. Just as an equation of the form a(b+c) = ab + ac is universally applicable and needs only to be filled in by numbers, the moral law must have an abstract formulation by which to test actions.

Kant had seized upon the idea of universalization as the key to the moral law. To universalize a principle of our action we ask, “what if everybody did this?” According to Kant, we should act according to a principle which we can universalize with consistency or without inconsistency. This is what he calls the categorical imperative. By testing the principle of our actions in this way, we determine if they are moral. If we can universalize our actions without any inconsistency, then they are moral; if we cannot do so, they are immoral.

For example, there is no logical inconsistency in universalizing the maxim, whenever we need a car we will work hard to earn the money. However, there is something inconsistent about universalizing the maxim, whenever we need a car we will steal it. A world where everyone stole cars would be a world where there were cars to steal but no cars to steal—since they would all already be stolen! (This is the basic idea, this is actually quite complicated.)

Of course, we can act contrary to reason because we are free, just like we can say that 2 + 2 = 6 or we can say that there are round squares. But we violate reason when we say these things just as, for example, bank robbers violate reason when they rob banks. Why?  A bank robber wills a world where:

  1. banks exists as the necessary prerequisite of the bank robbery intended and
  2. banks don’t exist as the obvious consequence of bank robberies.

Kant’s basic idea is something like this. If I say you can taste my wine, I should be able to taste yours. Moral actions are rational, immoral actions are irrational.

In short, we act ethically if we freely conform our will to the moral law which it understands as the categorical imperative. The imperative prescribes action that are rationally consistent. If we act in this way, we may not be happy, but we will be moral. We will have done our duty.

(You can find a more detailed summary of Kant’s ethics here.)

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13 thoughts on “Summary of Kant’s Ethics (short version)

  1. My offer to allow you to taste my wine is freely made, and rational, and universally applicable as anyone could offer another a taste of wine, just to share.

    There is no rational reciprocity in the altruistic action of offering a taste of wine.

    Perhaps you could have used a different source for your wine-tasting example: Do unto others as you would have them do unto you.

  2. The following phrase is unsupported and unnecessary: “The moral law ultimately comes from God”.
    You finish that sentence with “can be known by rational people.” This part is self evident.
    God is not needed for morality, as is clearly shown in the logical arguments within your article.

  3. 1. Without freedom, morality is not possible.
    2. Morality exists, thus
    3. Freedom exists.

    This is not a valid argument.

    (1) ~F –> ~◊M [P]
    (2) M [P]
    (3) F [?]

    Additionally, P2 is not taken by Kant to be self-evident. Evident, perhaps, but not self-evident.

    Furthermore, nowhere does Kant say that morality ultimately comes from God. Morality (for beings with a rational nature) ultimately comes from rational nature. On Kant’s view, God would be a perfectly rational being (i.e. has a “divine will”) and is therefore perfectly moral. The groundwork for the metaphysics of morals is not God–and there is an entire book of Kant’s that makes great efforts to explain the actual groundwork.

    To say that the categorical imperative can be expressed as “what if everybody did this?” is to present a misrepresentation. If this is the case, then what is Kant but a consequentialist?

    Granting the problematic interpretation of Kantian ethics as revolving around the categorical imperative as a sort of test procedure, the CI is certainly not a test of empirical consequence. The maxim of the car thief fails the CI procedure because a world where the concept of property coincides with–and is just as permissible as–the concept of theft results in a formal difficulty (of universal law), not in a material difficulty (e.g. all the cars would already be stolen).

  4. Appreciate your perceptive comments. I agree the argument isn’t valid. I also with your point about my formalization of the CI being consequentialist, but it is hard to understand imperfect duties in Kant (not helping others or developing your talents) without construing him as somewhat of a consequentialist. And I agree with your point about God and will make modifications after I research the issue to make sure. However Kant’s moral argument for God’s existence is (roughly) that there is a moral law so there must be a moral lawgiver. So I’m not completely sure of the connection. Thanks again for the comments.

  5. I like this as a summary of the “Groundwork” but don’t you think it’s a bit of an exaggeration to imply that this covers Kant’s ethics in two pages? Even as far as the Groundwork goes, this summary only touches on one of the formulations of the CI (leaving out the formulations according to rationality as an end in itself and the making of a kingdom of ends out of rational persons).

    I’m also unsure how I can square your consequentialist interpretation of the universalizability formulation of the CI and Kant’s own statements. Someone else already brought this point up but I’d like to comment on imperfect duties. Namely, Kant regards universalizability as there being no contradiction in the representation of a maxim of action as a law for all persons (as in, we must be able to will that our maxim is a law for all persons). For an imperfect duty, the contradiction is that we can’t will a violation of an imperfect duty to the degree that we can’t will that others do the same to us; as in, it is contradictory to will that action and also hold certain desires/expectations of the treatment of others.

  6. Obviously this is an attempt to cover Kant’s ethics in two pages for those who want that level of analysis. Obviously it falls short of more detailed analysis. As for imperfect duties, it might be that while perfect duties require a certain action—don’t lie—imperfect duties allow the duty to be fulfilled variously—develop your talents. But I don’t disagree with anything you say here. All I can add is that interpreting Kant is notoriously difficult.

  7. To my eyes, this looks more like an attempt to cover the “Groundwork of the Metaphysics of Morals” in two pages rather than Kant’s ethics in two pages (and I think it summarizes the Groundwork well, missing only some mention of people as ends in themselves). I did not mean to imply that you had attempted a detailed analysis of anything ; I only meant that your two page analysis covered something other than what you said that it covered in the title.

    Saying it attempts to cover Kant’s ethics is like saying that a summary of Book I and II of the “Nicomachean Ethics” (where he argues what makes people good) covers Aristotle’s ethics or that a summary of Mill’s argument for the principle of utility covers his ethics. The fact that the title was an exaggeration, since this only attempted to cover the basic principle of Kant’s ethics, was the main thing that I wanted to point out in my comment. I felt it was worth mentioning since it means the title is a little “clickbait-ey” and could leave readers thinking they had a rough idea of all of Kant’s ethics (as opposed to the rough idea this gives of his basic principle).

  8. you are correct, it is mostly about the groundwork, and an oversight on my part. thanks for pointing that out.

  9. 1.Without freedom, morality is not possible.
    2. Morality exists, thus
    3. Freedom exists.

    1. ~F->~M[P]
    2. F[P]
    3. M[P]

    actually freedom and morality is a bi-conditional
    the less freedom you have, the less moral obligations you have, the more freedom you will have.

    therefore world communism will restrict freedoms, and increase the moral obligations
    and the more free the society, the less moral obligations, and the increased freedoms.

  10. Thank you. I’ll actually read your detailed summary as well. I tried to read Kant directly some time ago but lost myself in the ‘maze’ quite soon 🙂

  11. Kant is very, very hard to read in the original. I had little luck with him myself in grad school and stuck mostly to secondary sources.

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