This is a handout I give my students when discussing Kant's categorical imperative. It's always astounded me how much confusion there is when it comes to discussing the organization of Kant's account of the formulations of the categorical imperative in the Groundwork. The discussion always seems to me to be quite lucid -- Kant gives the categorical imperative (the first on the list below) and then gives three formulations of it adapted to different kinds of moral vocabularies (the Law of Nature formulation, the End in Itself formulation, and the Kingdom of Ends formulation, which are the next three respecitvely), all three of which are supposed to be different ways of stating the one categorical imperative. Each of the formulations emphasizes a different aspect of the original statement of the categorical imperative (universality, maxim, and law, respectively).
But when you turn to discussions of it, it is remarkably how confused and confusing even some of the scholarship is. For instance, you find discussions where there are two 'Law of Nature formulations', where there is an Autonomy formulation that is distinct from the Kingdom of Ends formulation, etc. Many of these interpretive choices make no sense at all. For instance, the discussion of autonomy is quite clearly building up to the Kingdom of Ends, and Kant never actually gives a distinct 'Formula of Autonomy' at all -- the Kingdom of Ends formulation is the Autonomy formulation. There are many discussions that certainly get it right, but there are perhaps just as many that make a pig's breakfast of it, as well. And it can matter, since many of the criticisms that are made of Kant's account don't make much sense once you recognize how it is structured. For instance, people sometimes say the formulations are not equivalent, but recognizing that each formulation is simply emphasizing one of the elements of the categorical imperative makes it clear that Kant's claim that they are is at least plausible. If you chop up the discussion of the formulations in the wrong way, though, it wouldn't be surprising if you ended up with things that weren't equivalent.
Act only according to that maxim whereby you can at the same time will that it should become a universal law.
A ‘maxim’ is a “subjective principle of acting”; it is the rule someone makes in a decision that is based on their own circumstances and conditions.
Kant also summarizes this as: Always choose in such a way that the same willing includes the maxims of our choice as a universal law.
Act as if the maxim of your action were to become through your will a universal law of nature.
‘Nature’ in its broadest sense means everything that is determined by universal laws, so this formulation emphasizes the universality.
Kant also summarizes this as: Act on maxims that can at the same time have for their object themselves as universal laws of nature.
Act in such a way that you treat humanity, whether in your own person, or in the person of another, always at the same time as an end and never simply as a means.
An absolutely universal moral principle would have to be based on something whose existence is of absolute worth or value (something that could function as an ‘end in itself’); and this means value for every rational being precisely because they are rational. The only thing that can have worth for every rational being in this way is rational nature itself. Another way to put it: The only end that can be proposed by a moral law supposed to legislate for all rational beings in all possible circumstances is an end that is available to all rational beings in all possible circumstances. The only such end is rational nature itself.
This formulation emphasizes the maxim: the categorical imperative requires restricting our maxims so that they conform with universal law; this formulation recognizes that doing so requires restricting our maxims so that rational nature is always paramount.
Act according to the maxim of a universally legislating member of a merely possible kingdom of ends.
To recognize yourself as being an end in yourself, you must recognize that you, as a rational being, are legislating universally for all rational beings, independent of any interest or incentive.
By ‘kingdom’ is meant a society of different rational beings united by common laws. Since each rational being, as rational being, legislates universally for all rational beings, one can think of a kingdom whose members are each autonomous legislators, who are able to be united because they are all willing the same law; and for this law to be universal, it would have to treat rational nature as an end in itself. Thus such a society would be a ‘kingdom of ends’. It is said to be ‘merely possible’ because we are not talking about a society that actually exists, but only a society that we can form by our actions.
‘Autonomy’ is legislating for oneself; it is the opposite of ‘heteronomy’, receiving one’s laws from another. The only law that could be universally valid for all rational beings is the kind of law that rational beings legislate for themselves as rational beings. The only permissible actions, therefore, are those consistent with the autonomy of a rational will.
Worth is determined by law. Because rational beings are self-legislating ends in themselves, and thus are the source of law, they have absolute worth. This absolute worth is called ‘dignity’, a pricelessness that means nothing else can be substituted for them as being of equal or greater value. The only correct attitude toward something with the absolute worth of dignity is respect. It is because they have dignity that human beings are called ‘persons’.
Kinds of Moral Principle that Would be Heteronomous
Empirical (based on happiness)
Rational (based on perfection)
Relations of Perfection
Kant tells us that moral sentiment is a better candidate than private happiness, and relations of perfection a better candidate than divine will; neither moral sentiment nor relations of perfection weaken the force and authority of moral law, whereas private happiness and divine will do. Relations of perfection are a better candidate than moral sentiment because they are matters of pure reason. None of these, however, are capable of being a foundation for morality because they separate the source of moral law from the rational being who is supposed to follow moral law.