however, ethics were the great subject of his inquiries, to which
physics were only subordinate. The problem he sought to solve was the
way to live like the Deity; he would contemplate truth as the great aim
of life. With Aristotle, ethics formed only one branch of attention; his
main inquiries were in reference to physics and metaphysics. He thus, by
bringing these into the region of inquiry, paved the way for a new epoch
of scepticism.

Both Plato and Aristotle taught that reason alone can form science; but,
as we have said, Aristotle differed from his master respecting the
theory of ideas. He did not deny to ideas a _subjective_ existence, but
he did deny that they have an objective existence. He maintained that
individual things alone _exist_; and if individuals alone exist, they
can be known only by _sensation_. Sensation thus becomes the basis of
knowledge. Plato made _reason_ the basis of knowledge, but Aristotle
made _experience_ that basis. Plato directed man to the contemplation of
Ideas; Aristotle, to the observation of Nature. Instead of proceeding
synthetically and dialectically like Plato, he pursues an analytic
course. His method is hence inductive,--the derivation of certain
principles from a sum of given facts and phenomena. It would seem that
positive science began with Aristotle, since he maintained that
experience furnishes the principles of every science; but while his
conception was just, there was not at that time a sufficient amount of
experience from which to generalize with effect. It is only a most
extensive and exhaustive examination of the accuracy of a proposition
which will warrant secure reasoning upon it. Aristotle reasoned without
sufficient certainty of the major premise of his syllogisms.

Aristotle was the father of logic, and Hegel and Kant think there has
been no improvement upon it since his day. This became to him the real
organon of science. "He supposed it was not merely the instrument of
thought, but the instrument of investigation." Hence it was futile for
purposes of discovery, although important to aid processes of thought.
Induction and syllogism are the two great features of his system of
logic. The one sets out from particulars already known to arrive at a
conclusion; the other sets out from some general principle to arrive at
particulars. The latter more particularly characterized his logic, which
he presented in sixteen forms, the whole evincing much ingenuity and
s