Logic cannot have any empirical part; that is, a part in which the
universal and necessary laws of thought should rest on grounds taken
from experience; otherwise it would not be logic, i.e., a canon for
the understanding or the reason, valid for all thought, and capable of
demonstration. Natural and moral philosophy, on the contrary, can each
have their empirical part, since the former has to determine the
laws of nature as an object of experience; the latter the laws of
the human will, so far as it is affected by nature: the former,
however, being laws according to which everything does happen; the
latter, laws according to which everything ought to happen. Ethics,
however, must also consider the conditions under which what ought to
happen frequently does not.

We may call all philosophy empirical, so far as it is based on
grounds of experience: on the other band, that which delivers its
doctrines from a priori principles alone we may call pure
philosophy. When the latter is merely formal it is logic; if it is
restricted to definite objects of the understanding it is metaphysic.

In this way there arises the idea of a twofold metaphysic- a
metaphysic of nature and a metaphysic of morals. Physics will thus
have an empirical and also a rational part. It is the same with
Ethics; but here the empirical part might have the special name of
practical anthropology, the name morality being appropriated to the
rational part.

All trades, arts, and handiworks have gained by division of
labour, namely, when, instead of one man doing everything, each
confines himself to a certain kind of work distinct from others in the