otherwise we could not look for either certainty or purity in the
ethical teaching. To rely for this reason on a certain feeling
which, on account of the effect expected from it, is called moral,
may, perhaps, even satisfy the popular teacher, provided he desires as
the criterion of a moral duty to consider the problem: "If everyone in
every case made your maxim the universal law, how could this law be
consistent with itself?" But if it were merely feeling that made it
our duty to take this principle as a criterion, then this would not be
dictated by reason, but only adopted instinctively and therefore
blindly.

{PREFACE ^paragraph 5}

But in fact, whatever men imagine, no moral principle is based on
any feeling, but such a principle is really nothing else than an
obscurely conceived metaphysic which inheres in every man's
reasoning faculty; as the teacher will easily find who tries to
catechize his pupils in the Socratic method about the imperative of
duty and its application to the moral judgement of his actions. The
mode of stating it need not be always metaphysical, and the language
need not necessarily be scholastic, unless the pupil is to be
trained to be a philosopher. But the thought must go back to the
elements of metaphysics, without which we cannot expect any
certainty or purity, or even motive power in ethics.

If we deviate from this principle and begin from pathological, or
purely sensitive, or even moral feeling (from what is subjectively
practical instead of what is objective), that is, from the matter of
the will, the end, not from its form that is the law, in order from
thence to determine duties; then, certainly, there are no metaphysical