clearly and broadly between science and art is the following:--That the
principle of classification in science most conveniently follows the
classification of _causes_, while arts must necessarily be classified
according to the classification of the _effects_, the production of
which is their appropriate end. Now an effect, whether in physics or
morals, commonly depends upon a concurrence of causes, and it frequently
happens that several of these causes belong to different sciences. Thus
in the construction of engines upon the principles of the science of
_mechanics_, it is necessary to bear in mind the _chemical_ properties
of the material, such as its liability to oxydize; its electrical and
magnetic properties, and so forth. From this it follows that although
the necessary foundation of all art is science, that is, the knowledge
of the properties or laws of the objects upon which, and with which, the
art dons its work; it is not equally true that every art corresponds to
one particular science. Each art presupposes, not one science, but
science in general; or, at least, many distinct sciences.
(Editor's note:)
Essays on some Unsettled Questions of Political Economy
These five essays represent Mill's earliest thoughts on economic matters
and were first composed in 1829 and 1830 before his reputation had been
established by the publication of _Logic_ in 1843. Their successful
reception no doubt hastened the composition of his comprehensive work
the _Principles of Political Economy_ (1848).