Kant's Groundworks of the Metaphysic of Morals
In "Groundworks of the Metaphysic of Morals" Immanuel Kant proposes
that good will is the only thing which is good and that a person
should "act only under that maxim which he would will to be universal"
(273); Kant calls that test for morality the Categorical Imperative.
Kant believes that the CI can be formulated in several different
a. The Formula of Universal Law
b. The Formula of the End in Itself
c. The Formula of the Kingdom of Ends
Kant upheld scientific laws as the model rational principles. A
characteristic of scientific laws is that they are universal, such as
the law that when heated, gas will expand. Kant thought that moral
laws or principles must have universality to be rational. Kant derives
the categorical imperative out of the notion that we should be willing
to adopt those moral principle that can be universalized, that is,
those which we can imagine that everyone could act upon or adopt as
their principle. Thus the first formulation of the categorical
imperative is: "Act only on that maxim which you can will as a
universal law." or the Formula of Universal Law. Consider the example
Kant gives of giving a false promise. Making false promises is wrong,
because it can not imagine everyone adopting this as a principle of
action. If everyone did, then promising would make no sense
i. Cases in which there simply could not be a world in which everyone
acts on the maxim because everyone's trying would be destructive of
everyone's continuing ability to do so: "Some actions are so
constituted that their maxim cannot even be conceived as a universal
law of nature without contradiction."
ii. Cases where one can conceive of a world in which everyone
acts on the maxim, but where one cannot consistently or rationally
will such a world.
In either kind of case, the maxim will fail the CI test. According to
Kant, it would be wrong to act on a maxim of either kind.
Kant gives examples of both kinds:
i.: A person proposes to make a promise he doesn't intend to keep to
pay back money in order to meet a need of his own. He must consider
whether he could will a world in which everyone is motivated in
precisely the same way. Kant claims that he cannot since it is only
possible for people to promise in the first place if there is
sufficient trust for others to believe that the person promising
intends to keep his promise. But a world (otherwise like our own) in
which everyone acted on this maxim would be a world in which such
trust will not exist. Therefore it is impossible even to conceive of a
world in which everyone acts on this maxim as though by a law of
nature; therefore it is wrong to act on this maxim oneself.
Note this example also illustrates the idea of a contradiction in