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

FALLACIES. 321
a true e Xey^o? must disprove." Jevons truly says,
" The
fallacy usually occurs in the course of long harangues,
where the multitude of words and figures leaves room
for confusion of thought and forgetfulness. . . . This
fallacy is, in fact, the great resource of those who have
to support a weak case. It is not unknown in the legal
profession, and an attorney for the defendant in a law
suit is said to have handed to the barrister his brief
marked, No case; abuse the plaintiff s attorney. Who
ever thus uses what is known as argumentum ad hom-
inem that is, an argument which rests, not upon the
merit of the case, but the character or position of those
engaged in it commits this fallacy. If a man is ac
cused of a crime, it is no answer to say that the pros
ecutor is as bad. If a great change in the law is
proposed in Parliament, it is an Irrelevant Conclusion
to argue that the proposer is not the right man to bring
it forward. Every one who gives advice lays himself
open to the retort that he who preaches ought to
practise, or that those who live in glass houses ought
not to throw stones. Nevertheless there is no neces
sary connection between the character of the person
giving advice and the goodness of the advice.
"
The argumentum ad populum is another form of Ir
relevant Conclusion, and consists in addressing argu
ments to a body of people calculated to excite their
feelings and prevent them from forming a dispassionate
judgment upon the matter in hand. It is the great
weapon of rhetoricians and demagogues."
To these we may add what is called the argumentum
ad ignorantiam, trading on the ignorance of the person
or persons addressed ; the argumentum ad verecundiam,
an appeal to veneration for authority instead of to
reason ; and the argumentum ad baculum, which is
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