The Critique of Practical Reason is
teh second of the Kant's three critiques. It contains two sections:
the Doctrine of Elements(containing the Analytic of Pure Practical
Reason) and the Dialectic of Pure Practical Reason.
- The Analytic contains the arguments
for the categorical imperative as the one true moral principle and
for the identity of morality and freedom.
- The Dialectic exposes the primary
error of all previous ethicists and proposes the postulates of pure
practical reason.
- The Doctrine of Method proposes a
new method for moral education.
- The Analytic, which is set up like
a geometric proof, takes several steps to reach its primary
conclusion, that the one ultimate moral principle is to only act
such that the maxim of your will could hold universally.
- A law, Kant says, must be necessary
and universal, for otherwise it is no law. If that is so, though,
its force cannot be dependent on any contingent feature of the
person following it.
- Next he argues that any law whose
force was supposed to depend on its content would run afoul of this
if we tried to say that obedience to God was the ultimate moral
law, we could not, for this law could only hold for those who
wanted to obey God.
- The Analytic now goes on to argue
that the free person and the moral person are one and the same. The
free person acts on a law, and not randomly, but not an externally
given law, for that would be a form of slavery. Only the
categorical imperative is found suitable. Conversely, the moral
person is following the practical law and is not bound by
contingent desires, and so is autonomous.
- The Dialectic accuses all previous
ethical writers of having made the same mistake, the mistake of
having regarded the morally worthy as aiming at the highest good
instead of seeing the highest good as that which is aimed at by
morality. These ethical systems were doomed to fail because the
moral will cannot be constrained by an independent highest good,
since for it to seek anything independent of itself would be to
constrain its freedom.
- We understand our freedom which
would otherwise be undetectable while following the moral law. This
following of the moral law frees us from the control of our
desires. Our ability to feel the force of the practical law is also
how we come to know that there is such a law. Therefore, the
conclusions about this law, reached in the beginning of the
Analytic, are not merely hypothetical. In arguing thus for the
reality of morality and freedom, Kant reverses the order of
evidence he had in his earlier Groundwork for the Metaphysics of
Morals, where he derived morality from freedom.
- Finally, in the Doctrine of Method,
Kant proposes a method for teaching morality. It is essential to
teach the student to act from duty, and not merely outwardly,
conforming to morality. Kant recommends that we enlist our pupil's
natural delight in arguing about ethical matters and allow him to
develop his judgment by asserting various purported moral
actions.