Kant's Moral Philosophy (Part II)

1 The Categorical Imperative
The main point of Kant's Moral Philosophy is the Categorical Imperative, which is the supreme principle of Morality. All moral principles are derived from it.
- Imperative is a command, that is expressed by an ought. “Imperatives say that something would be good to do or to refrain from doing” (p. 24 [413]) An imperative takes the grammatical form of “should”/“ought”.
- Distinction hypothetical and categorical imperative: A hypothetical imperative is conditioned, i.e. says only “that an action is good for some purpose” (p. 25 [414]). A categorical imperative “holds as an apodeictic (practical) principle.”(p. 25 [415])
- The main form of the categorical imperative: “Act only according to that maxim whereby you can at the same time will that it should become a universal law.” (p. 30 [421])
Out of the main form, different formulas of the categorical imperatives can be derived:
- Categorical imperative of duty (or: formula of the law of nature): “Act as if the maxim of your action were to become through your will a universal law of nature” (p. 30 [421])
- Formula of the end in itself: “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.” (p. 36 [429], reformulation p. 37 [433])

2 Application of the Categorical Imperative
How to judge an action: a) Find the person’s subjective maxim (e.g. “I always lie, when I can take out profit.”), b) try to imagine a world, where everybody acts accordingly, c) find out whether contradictions or irrationalities result, d) if yes, the action is not allowed; if no, the action is allowed or even required.
Perfect duty: To not act according to maxims, which results in a logical contradiction, when we try to universalize them. The proposition “Lying is permissible”, if universalized, would lead to the destruction of the institution of language; similarly the universalized proposition “stealing is permissible”, would undermine the institution of having property.
Imperfect duty: To act according to maxims, which we would like to be universalized. The subjective maxim “Never help someone else, when in need” would, if universalized, not lead to a logical contradiction, but to a “contradiction of the will” as Kant calls it, i.e. we can not will a world where this propostion would be true.
Note: The perfect duty is stronger, then the imperfect one. The imperfect one is relative to preferences.

3 Kant’s anthropological claims with regard to moral philosophy
Man is an end in himself: Is there something which has absolute worth? Yes: man, i.e. all rational beings have to be regarded not only as a means but “at the same time as an end” (p. 35 [428]).
Explanation: Persons exist as ends in themselves; there is no substitution possible of one man through an other. This is because: “rational nature exists as an end in itself. In this way man necessarily thinks of his own existence; thus far is it a subjective principle of human actions.” (p. 36 [429]) And it is the objective principle, because we think of other humans as rational as well.
Kingdom of Ends: is a regulative idea that concretizes the formula of the end in itself. A kingdom of ends would be established if different rational beings live together by common and universal laws they have given to themselves. The kingdom of ends would then consist out of a) the rational beings as ends and b) the particular ends the people set for themselves (p. 39 [433])
Autonomy: At the center of a rational being is his autonomy: “Hence Autonomy is the ground of the dignity of human nature and of every rational nature.” (p. 41 [436])