FOUNDATIONS OF THE METAPHYSICS
OF MORALS
PREFACE
Ancient Greek philosophy was divided into three sciences: physics, ethics, and logic.
This division conforms perfectly to the nature of the subject, and one need improve on
it perhaps only by supplying its principle in order both to insure its exhaustiveness and
to define correctly the necessary subdivisions.
All rational knowledge is either material, and concerns some object, or formal, and is
occupied only with the form of understanding and reason itself and with the universal rules
of thinking, without regard to distinctions among objects. Formal philosophy is called
logic. Material philosophy, however, which has to do with definite objects and the laws to
which they are subject, is divided into two parts. This is because these laws are either laws
of nature or laws of freedom. The science of the former is called physics, and that of the lat-
ter ethics. The former is also called theory of nature and the latter theory of morals.
Logic can have no empirical part—a part in which universal and necessary laws of
thinking would rest upon grounds taken from experience. For in that case it would not be
logic (i.e., a canon for understanding or reason which is valid for all thinking and which
must be demonstrated). Natural and moral philosophy, on the other hand, can each have
its empirical part. The former must do so, for it must determine the laws of nature as an
object of experience, and the latter must do so because it must determine the human will
so far as it is affected by nature. The laws of the former are laws according to which every-
thing happens; those of the latter are laws according to which everything ought to
happen, but allow for conditions under which what ought to happen often does not.
All philosophy, so far as it is based on experience, may be called empirical; but,
so far as it presents its doctrines solely on the basis of a prioriprinciples, it may be
called pure philosophy. Pure philosophy, when formal only, is logic; when limited to
definite objects of the understanding, it is metaphysics.
In this way there arises the idea of a two-fold metaphysics—a metaphysics of
nature and a metaphysics of morals. Physics, therefore, will have an empirical part and
also a rational part, and ethics likewise. In ethics, however, the empirical part may be
called more specifically practical anthropology; the rational part, morals proper.
All crafts, handiworks, and arts have gained by the division of labor, for when one
person does not do everything but each limits himself to a particular job which is distin-
guished from all the others by the treatment it requires, he can do it with greater perfec-
tion and more facility. Where work is not thus differentiated and divided, where
everyone is a jack-of-all-trades, the crafts remain at a primitive level. It might be worth
considering whether pure philosophy in each of its parts does not require a man partic-
ularly devoted to it, and whether it would not be better for the learned profession as a
whole to warn those who are in the habit of catering to the taste of the public by mixing
up the empirical with the rational in all sorts of proportions which they themselves do
FOUNDATIONS OF THEMETAPHYSICS OFMORALS 851
388387Immanuel Kant,Foundations of the Metaphysics of Morals,2nd ed., translated by Lewis White Beck
(Pearson/Library of the Liberal Arts, 1989).