Categorical Imperative - The Second Formulation

The Second Formulation

Every rational action must set before itself not only a principle, but also an end. Most ends are of a subjective kind, because they need only be pursued if they are in line with some particular hypothetical imperative that a person may choose to adopt. For an end to be objective, it would be necessary that we categorically pursue it.

The free will is the source of all rational action. But to treat it as a subjective end is to deny the possibility of freedom in general. Because the autonomous will is the one and only source of moral action, it would contradict the first formulation to claim that a person is merely a means to some other end, rather than always an end in themselves.

On this basis, Kant derives second formulation of the categorical imperative from the first.

By combining this formulation with the first, we learn that a person has perfect duty not to use the humanity of themselves or others merely as a means to some other end. As a slaveowner would be effectively asserting a moral right to own a person as a slave, they would be asserting a property right in another person. But this would violate the categorical imperative because it denies the basis for there to be free rational action at all; it denies the status of a person as an end in themselves. One cannot, on Kant's account, ever suppose a right to treat another person as a mere means to an end.

The second formulation also leads to the imperfect duty to further the ends of ourselves and others. If any person desires perfection in themselves or others, it would be their moral duty to seek that end for all people equally, so long as that end does not contradict perfect duty.