An introductory text-book of logic - Mellone, Sydney - Rare Books at ...

6 THE GENERAL AIM OF LOGIC.
tion and explanation of Nature. In this work inquiry
into principles of scientific method Roger Bacon
(1214-1294) was a brilliant forerunner of writers much
later in date. Francis Bacon, the Chancellor, carried
on the work, and wrote his Novum Organum in rivalry
with what he thought was the Aristotelian system of Logic.
It was natural that as this seemed to be a new beginning
in Logic, a new name should be found for it ;
and during
Inductive Logic," as it is called,
"
the nineteenth century,
has received much attention. The most important works
in which it has been developed are those of Herschel,
Whewell, and John Stuart Mill.
Hence the usual treatment of Logic lays out the subject
in two branches. The first of these is founded on the Logicwhich
the mediaeval writers developed out of such acquaint
ance with Aristotle as they possessed. This is usually called
"
"
Deductive Logic
or
"
Formal Logic." The second
"
division is the Inductive Logic" of which we have spoken,
which is often called
"
Material Logic." So far as the dis
tinction implies a difference in principle between the two
kinds of knowledge,
it has no foundation in the facts of
thought ; otherwise, there are advantages in not departing
from it. 1
4. Logic has to consider Language ; but only so
far as differences of expression in language are the
embodiment of differences of type in the process of
thought. The word X6yo<s had a double meaning in
Greek : (a) the thought^ (/>) the word (or rather, phrase
or sentence) which is the expression of the thought,
ratio and oratio. Aristotle distinguished these, calling
the former TOV lo-co, TOV lv and the latter
rfj TOV tn>
i/o^??, ;
the
"
"
inward and the
"
"
outward
logos. This am
biguity has given rise to a dispute as to whether Logic
1 The recent philosophical development of Logic will be re
ferred to in our concluding chapter, I.