e liable to certain errors. To protect against
the one is the main end of "Deductive" Logic: to protect against the
other is the main end of "Inductive" Logic. As a matter of fact the
pith of treatises on Deduction and Induction is directed to those ends
respectively, the old meanings of Deduction and Induction as formal
processes (to be explained afterwards) being virtually ignored.

There is thus no antagonism whatever between the two branches of
Logic. They are directed to different ends. The one is supplementary
to the other. The one cannot supersede the other.

Aristotelian Logic can never become superfluous as long as men are apt
to be led astray by words. Its ultimate business is to safeguard in
the interpretation of the tradition of language. The mere syllogistic,
the bare forms of equivalent or consistent expression, have a very
limited utility, as we shall see. But by cogent sequence syllogism
leads to proposition, and proposition to term, and term to a close
study of the relations between words and thoughts and things.

[Footnote 1: We know for certain--and it is one of the
evidences of the importance attached to this trivial-looking
pastime--that two of the great teacher's logical treatises,
the Topics and the Sophistical Refutations, were written
especially for the guidance of Questioners and Respondents.
The one instructs the disputant how to qualify himself
methodically for discussion before an ordinary audience, when
the admissions extracted from the respondent are matters of
common belief, the questioner's skill being directed to make
it appear that the respondent's position is inconsistent
with these. The other is a systematic exposure of sophistical
tricks, mostly verbal quibbles, whereby a delusive appearance
of victory in debate may be obtained. But in the concluding
chapter of the _Elenchi_, where Aristotle claims not only
that his method is superior to the empirical methods of
rival teachers, but that it is entirely original, it is the
Syllogism upon which he lays stress as his peculiar and
chief invention. The Syllogism, the pure forms of which are
expounded in his Prior Analytics, is really the centre of
Aristotle's logical system, whether the propositions to
which it is applied are matters of scientific truth as in the
Posterior Analytics, or matters of common opinion as in
the Topics. The treatise o