Architecture and the fine arts, fulfil themselves in such an object.
Medicine, agriculture and similar professions, however, are auxiliary
arts, and obey the laws of nature, assisting their efficient production
so as to make them as natural as possible. As to rhetoric, music,
and other arts of refinement, which serve the education of souls in
improving or degrading men, it remains an open question how many there
are of them, and what power they possess. In all these things, we will
have to examine what may be of use to us for the questions we are
treating, and we will have to discover the cause of the facts, as far
as possible.