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

AND THE ARISTOTELIAN SYLLOGISM. 141
Hence we may explain the liability of thick glass to crack
more easily than thin glass, when heated :
Hotter substances expand more than those that are less
heated ;
When thick glass is heated, the surface is (at first) hotter
than the interior ;
Hence the surface expands more than the interior.
In all such reasoning, the major premise (the general law)
is supposed to be known independently of this particular
case to which we apply it. In the following example, New
ton discovered the major premise by mathematical cal
culation :
Whenever one body revolves round another which attracts
with a force decreasing as the square of the distance
increases, it will describe an orbit of which Kepler s
Laws are true.
The planets are bodies holding this relation to the sun ;
Therefore the planets describe orbits of which Kepler s
Laws are true.
In Grammar, every application of a grammatical rule to
the construction of a sentence is a syllogism in Barbara.
In Ethics, all appeals to accepted moral rules in judging
particular acts are syllogisms in fig. i. ; and if the result is
affirmative, the mood is the same fundamental one. 1 In
Law, the procedure is equally syllogistic.
" The whole aim
of legal procedure is to determine whether a particular case
does or does not fall under a given general rule. Thus, in
a criminal trial, the law which has been violated furnishes
the major premise, and the examination of the acts of the
accused supplies the minor premise." In Economics, the
whole "Deductive Method" is an application of general
rules to cases coming under them, and therefore consists in
a continual use of the mood Barbara. In History, explan
ation by general laws is resorted to whenever possible.
Our knowledge of human nature individual and social sup
plies various major premises, of what men and nations will
do under given circumstances and ; having found historical
1 It is worth noting that our words "principle" and "maxim"
(prcemissa maxima) are survivals from the Aristotelian "practical
syllogism" (Eth. Nic., vii. 3).