hat no certain conclusion can be drawn except
upon this condition, is apt to dismiss the argument as altogether
worthless. This may be specified as an error incident to the practice
of the Syllogism, that it inclines us to look for necessarily
conclusive premisses, and to deny all weight to anything short of
this. Now in ordinary life it is comparatively seldom that such
premisses can be found. We are obliged to proceed on maxims that are
not of universal scope, and which lend only a more or less strong
colour of probability to cases that can be brought under them. "A
little learning is a dangerous thing;" "Haste makes waste;" "Slowness
of speech is a sign of depth of thought;" "Vivacity is a sign of
shallowness:" such are the "endoxes" or commonplaces of popular
knowledge that men bring to bear in daily life. They are not true for
all cases, but some of them are true for most or for a good many, and
they may be applied with a certain probability though they are not
rigidly conclusive. The plain man's danger is that he apply them
unthinkingly as universals: the formal logician's danger is that,
seeing them to be inapplicable as universals, he dismisses them as
being void of all argumentative force.
It helps to fix the limits of Formal Logic to remember that it lies
outside its bounds to determine the degree of probability attaching
to the application of approximate truths, such as are the staple of
arguments in ordinary affairs. Formal Logic, we may repeat, is
not concerned with degrees of truth or falsehood, probability
or improbability. It merely shows the interdependency of certain
arguments, the consistency of conclusion with premisses.
This, however, is a function that might easily be underrated. Its
value is more indirect than direct. In showing what is required for a
certain conclusion, it puts us on the road to a more exact estimate of
the premisses alleged, a sounder judgment of their worth. Well begun
is half done: in undertaking the examination of any argument from
authority, a formal syllogism is a good beginning.
CHAPTER VII.
CONDITIONAL ARGUMENTS.--HYPOTHETICAL SYLLOGISM, DISJUNCTIVE SYLLOGISM,
AND DILEMMA.
The justification of including these forms of argument in Logic is
simply that they are sometimes used in debate, and that confusion
may arise unless the precise meaning of the premisses employed
is understood. Aristotle did not include them as now given in his
exposition of the Syllog
|