92 Moral Philosophy: Ideas of Good and Evil, Right and WrongKant then introduces the concept of maxims. A maxim is a
subjective principle for action. There are two kinds of maxims,
material and formal. A material maxim is one in which the actor
has a motive and seeks some particular result. Since a good will
cannot be concerned with results, since moral acts are good (or
bad) regardless of results, the material maxim is insufficient to
produce moral worth. Therefore, Kant introduces the formal
maxim. The formal maxim is a principle for acting regardless of
desire, self interest, results, or consequences. If one acts on the
formal maxim for the sake of duty, then the act has moral worth.
Kant’s supreme law of morality is the categorical imperative,
which is the product of applying the formal maxim according to
this principle: “I ought never to act except in such a way that I can
will that my maxim should become a universal law.” If one is
about to act on a subjective principle, which he has free will to
do or not to do, Kant requires that one simply ask, “what would
happen if this act, which I am about to choose to do, were to
become a universal law, which all others in my circumstance
would have to do?” If, indeed, one were to apply this categorical
imperative, knowing what should or should not be done would
be obvious.
There are, according to Kant, three kinds of imperatives—
problematic hypothetical imperatives (rules of skill), assertoric
hypothetical imperatives (counsels of prudence), apodeitic cat
egorical imperatives (laws of morality). Problematic hypotheti
cal imperatives involve actions that are good only as a means to
something else. They are used simply because of the desirability
of the end, whatever that end might be. Assertoric hypothetical
imperatives are also geared to the attainment of some end, but a
natural end such as happiness. An example of a rule of skill
would be, “If you wish to learn to play the piano, you must
practice.” An example of a counsel of prudence would be, “If
you wish to be healthy, you should eat wisely.” Neither of these
hypothetical imperatives deals with the moral law. Only the
categorical imperative can serve as moral law.
The categorical imperative is an unconditional moral com
mand. It holds true in all circumstances, on all occasions,
regardless of consequences, desires, or qualifications. If it holds
in one instance, it holds in all. It is universal. If, for example, one
is faced with the opportunity to lie for convenience’ sake, by