Categorical imperative is a command, which expresses a general, unavoid¬able requirement of the moral law. In its three forms, are expressed the requirements of
2. respect and
Together they establish that an action is properly called 'morally good' only if
(1) we can will all persons to do it,
(2) it enables us to treat other persons as ends and not merely as the means to our own selfish ends, and
(3) it allows us to see other persons as mutual law-makers in an ideal 'realm of ends'.
Kant says that:
Nothing is absolutely good except a good will. The will is practical reason, i.e. the ability to act according to principles. So the best will (the purest will) is the most principled or rule-governed will. A good will is a rational will.
What does a rational (i.e. good) will? Rationality or principledness itself, obedience to exceptionless law.
The moral law: "I am never to act otherwise than so that I could also will that my maxim should become a universal law." To do otherwise would be illogical. If I make an exception to permitting stealing then I could never expect my belongings to be secure.
A maxim is a principle or motive of action.
The will is subject to (i.e. can be moved by) subjective impulses and objective principles. Nothing done on impulse, even a good impulse, has moral worth. Only actions performed on principle, out of a sense of duty, have genuine moral worth or value.
Rational action:These are actions where the will obeys the command of reason. Rational actions can be of two kinds:
a) Action according to a hypothetical imperative, or
b) Action according to a categorical imperative.
Hypothetical imperatives are based on subjective desires or preferences. E.g. if you want avoid a heart attack, one way to prevent heart disease may be to start exercising.
A categorical imperative form of this command or imperative would be: Exercise!
There is one categorical imperative, only one thing that every rational being must do. This one thing can be expressed in different ways, e.g.:
"Act only on that maxim whereby you can at the same time will that it should become a universal law."
"Act as if the maxim of your action were to become by your will a universal law of nature."
"So act as to treat humanity [i.e. rational nature], whether in your own person or in that of another, in every case as an end. . ., never as means only. . .."
These three ways are different rules or tests, to put the proposed action to, to see if it meets the categorical imperative (as opposed to the hypothetical). This is where it gets tricky. There is a categorical imperative. And then to test your proposed categorical imperative, it must meet three tests. These tests are in turn called categorical imperatives. In fact they are tests of the categorical imperative. But to stay in line with textbooks and Kant, they are called th4e three categorical imperatives. Kant gives 4 examples of the categorical imperative in action; involving duties to self, duties to others, perfect duties (i.e. duties that apply all the time) and imperfect duties (i.e. duties that we only have to obey some of the time).
1) Perfect duty to self:
Examples: Do not commit suicide. Do not get drunk so you are