I am trying to understand Kant's Second Categorical Imperative:

Act in such a way that you treat humanity, whether in your own person or in the person of any other, never merely as a means to an end.

The way I understood it: While using others, one must respect the humanity in others and remember that they are an end to themselves and not a means to our end alone.

My question is: What exact changes is one supposed to bring to the way in which he uses others, given that others are not "mere means"?

  • "Mere means" and "Merely as means" maybe sound similar but former implies that some means mere and others are not. Latter implies that treating anyone just as means (whatever these means are) itself is not proper, you must treat them as ends.
    – rus9384
    Commented Apr 24, 2018 at 14:12

3 Answers 3


Kant himself offers ideas of how to apply the formula in Ak. 429-30. I will quote and parse the text in order to highlight the guidance he himself has given for this particular formula (translations from Kant, I. (1785/2011), Groundwork of the metaphysics of morals: A German–English edition (M. Gregor & J. Timmermann, Trans.), Cambridge, MA: Cambridge University Press):

1. The human being is not a thing at anyone's disposal

First, according to the concept of necessary duty to oneself, someone who is contemplating self-murder Will ask himself Whether his action can be consistent With the idea of humanity, as an end in itself. If to escape from a troublesome condition he destroys himself, he makes use of a person, merely as a means, to preserving a bearable condition up to the end of life. But a human being is not a thing, hence not something that can be used merely as a means, but must in all his action always be considered as an end in itself. Thus the human being in my own person is not at my disposal, so as to maim, to corrupt, or to kill him. (Ak. 429, bolded mine)

Here, the punchline is "a human being is not a thing" as well as not being "at my disposal", but further specifics are not given beyond the "end in itself" idea. It is just clear that one should not see the human body itself and its abilities (e.g. working power etc.) as a mere mechanical factor just like any other physical object (similar to Heidegger's Dasein vs. Sein). So there are only hints so far.

2. One does not have the rights (or "principles") of others at one's disposal

Secondly, as far as necessary or owed duty to others is concerned, someone Who has it in mind to make a lying promise to others will see at once that he wants to make use of another human being merely as a means, who does not at the same time contain in himself the end. For the one l want to use for my purposes by such a promise cannot possibly agree to my way of proceeding with him and thus himself contain the end of this action. This conflict with the principle of other human beings can be seen more distinctly if one introduces examples of attacks on the freedom and property of others. For then it is clear that the transgressor of the rights of human beings is disposed to make use of the person of others merely as a means, without taking into consideration that, as rational beings, they are always to be esteemed at the same time as ends, i.e. only as beings who must, of just the same action, also be able to contain in themselves the end* (Ak. 429-30)

Here, Kant gets more specific in two senses: First, he makes clear that it is about human beings being the (autonomous, but this is at a later stage of the argument) agents of their own principles and rights. And secondly, they must, as rational beings, always be able to see themselves as an (autonomous) agent of these principles and rights, given they knew all relevant circumstances of the situation. In other words: It should be reasonable that if they had the choice and knew the facts, they would be ok with you acting the way you do.

The latter formulation may lead to some misconceptions. The asterisk at the end of the paragraph leads to a very important footnote where Kant explicitly distances himself from the well-known Golden Rule ("Do unto others as you would have them do unto you.", see e.g. the Bible Tobit 4:15, Matthew 7:12 and Luke 6:31). The point here is that it is not about what you would like to be treated, but the other one, and only insofar they are a rational agent (since you cannot and should not guess what a particular person actually likes or needs to be happy, as most people do not even know it themselves, cf. Ak. 417-8). This solves alleged problems of the principle regarding S/M-people etc. which are prominent in literature as well as certain forms of enjoying prostitution and other problematic cases the Golden Rule is open for.

3. It involves acting for the betterment of all humanity

Thirdly, with regard to contingent (meritorious) duty to oneself it is not enough that the action not conflict with humanity in our person, as an end in itself, it must also harmonize with it. Now there are in humanity predispositions to greater perfection, which belong to the end of nature with regard to humanity in our subject; to neglect these would perhaps be consistent with the preservation of humanity, as an end in itself, but not with the advancement of this end.

Here, the idea is that you have a moral responsibility for all humanity, i.e. you should work to advance all concerns of human beings to the best of your ability in all your actions, including widening your knowledge and abilities to the best of your natural features in order to be able to do so in the first place.

4. The same is true for the happiness and concerns of all others

Fourthly, as concerns meritorious duty to others, the natural end that all human beings have is their own happiness. Now, humanity could indeed subsist if no one contributed anything to the happiness of others while not intentionally detracting anything from it; but this is still only a negative and not positive agreement with humanity, as an end in , itself, if everyone does not also try, as far as he can, to advance the ends of others. For if that representation is to have its full effect in me, the ends of a subject that is an end in itself must, as much as possible, also be my ends.

This is interwoven with the third point, as you will probably already have understood from my wording of the interpretation there read together with the quote. The idea here is the same: We have a duty to work for the better of all humanity since humanity is an end in itself (we are insofar we take part in being human/rational agents). The difference is that here, it is not just about doing everything to be able to do so by working hard to better yourself, but now also actively engaging in the betterment for and of others.


Kant himself highlights four aspects of the formula:

1) A human being (i.e. his body, life, working power, etc.) is not a mere thing that is at disposal.

2a) This is because every human is the agent of his own principles and rights.

2b) Hence, we must (negatively) respect the other human's ability to decide what he wants and treat him in a way we can reasonably expect a rational agent (not the particular person or yourself) to be able to agree with, given he knows all relevant facts.

3) Furthermore, we are (positively) responsible to work on ourselves to be able to do the best we can for the betterment of all humanity since this is what we rationally, as part of humanity, would and can expect from any rational agent.

4) In an extension of working on ourselves, our responsibility to do our best for all humanity applies to actively engaging with all humans (i.e. rational beings) and their concerns.

While the first two/three aspects are about negative duties (you should not) and more or less understandable and applicable insofar as they just exclude certain determinate ways of action, the latter two are a bit woolly and admittedly do not help much in determining a particular action.


Kant's moral theory depends on there being an objective (end) and an action to fulfill it. Kant's first maxim flows from universality -

"Act only according to that maxim whereby you can at the same time will that it should become a universal law."

Treating people as end in themselves, rather than means, simply means to have an objective with an end goal involving the person. A fine example would the distinction between slavery and labour. In case of slavery, the slave is merely means to an end of making profits. However, with a labourer, the owner of the company may have another end, i.e., paying the labourer, his fair share.

In both the cases, the universal principle is profit maximisation. However, in the first case, other humans are disposable tools towards that end. By presence of a second principle that "people should get their fair share", some ways to maximise profit can be dismissed.

"never merely as a means to an end" does not suggest that humans should never be used as means, but the means in which they are treated should be subject to the first principle ("Categorical Imperative"), in which their perspective is an end in itself.

What exact changes is one supposed to bring to the way in which he uses others, given that others are not "mere means"?

As long as you have a goal with an end involving the people that you are using, such that if it becomes a universal law (and thus, applicable on you too), you have no problem, but you actually will that for yourself, then you are fine.


The full quote is (Kant, Immanuel: Groundlaying toward the Metayphsics of Moral, 2nd edition 1786):

Act in this way, that you use humanity in your own person, as well as in the person of every other, always at the same time as an end, never merely as a means.

Unfortunately, your quote dismisses the positive part "as an end". To respect other persons "as an end" means to respect that they have their own goals, which are of equal validity like my goals.

That's the basic interpretation. But Kant also intends a much more abstract meaning when referring to "humanity".

Added due to @rus9384's comment: If your question is "how such way of thought should/may affect behavior?", then the pragmatic basic answer is: Ask yourself which goals has the person himself, whom you use to obtain your own goals? Are the goals compatible?

  • Well, maybe their quote misses it, questioner explicitly pointed that they understand that this is what Kant meant: "While using others, one must respect the humanity in others and remember that they are an end to themselves and not a means to our end alone." So, the question is rather how such way of thought should/may affect behavior, I think.
    – rus9384
    Commented Apr 24, 2018 at 16:18
  • @JoWehler Kant has magnificently been able to state a lot of morality abstractly. The way people should use other people, given that others have their own goals, also be stated in an abstract and general manner?
    – BlowMaMind
    Commented Apr 25, 2018 at 4:30
  • Please see the long answer of @Philip Klöcking to your original question.
    – Jo Wehler
    Commented Apr 25, 2018 at 15:53

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .