various consequences without absurdity, if we are
content with poetic consistency and the authority of myths and romances
as the test of truth.

In the region of concrete objects, whose properties are causes, and
neither merely fictions nor determinations of space (as in Geometry), we
meet with another condition of the validity of any argument depending on
a definition: there must not only be objects corresponding to the
definition, but there must be no other causes counteracting those
qualities on whose agency our argument relies. Thus, though we may infer
from the quality of co-operation connoted by civilisation, that a
civilised country will be a wealthy one, this may not be found true of
such a country recently devastated by war or other calamity. Nor can
co-operation always triumph over disadvantageous circumstances.
Scandinavia is so poor in the gifts of nature favourable to industry,
that it is not wealthy in spite of civilisation: still, it is far
wealthier than it would be in the hands of a barbarous people. In short,
when arguing from a definition, we can only infer the _tendency_ of any
causal characteristics included in it; the unqualified realisation of
such a tendency must depend upon the absence of counteracting causes. As
soon as we leave the region of pure conceptions and make any attempt to
bring our speculations home to the actual phenomena of nature or of
human life, the verification of every inference becomes an unremitting
obligation.

CHAPTER XXIV

FALLACIES

Sec. 1. A Fallacy is any failure to fulfil the conditions of proof. If we
neglect or mistake the conditions of proof unintentionally, whether in
our private meditations or in addressing others, it is a Paralogism: but
if we endeavour to pass off upon others evidence or argument which we
know or suspect to be unsound, it is a Sophism.

Fallacies, whether paralogisms or sophisms, may be divided into two
classes: (a) the Formal, or those that can be shown to conflict with one
or more of the truths of Logic, whether Deductive or Inductive; as if we
attempt to prove an universal affirmative in the Third Figure; or to
argue that, as the average expectation of life for males at the age of
20 is 19-1/2 years, therefore Alcibiades, being 20 years of age, will
die when he is 39-1/2; (b) the Material, or those that cannot be clearly
exhibited as transgressions of any logical principle, but are due to
superficial inquiry or confused reason