Ad Hominem Fallacies

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Ad Hominem Fallacies

• Focusing on PeopleInstead of Ideas

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Ad Hominem FallaciesAbout persons instead of
premises

• Personal attack
• Inconsistency (incl. double standard)
• Circumstantial (positive or negative)
• Poisoning the well
• Genetic Fallacy
• Favoritism
• Tu quoque (and you too...)

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Ad Hominem FallaciesPersonal Attack
The personal attack looks like just what its name
suggests. Critical thinking does not take the
position that we should always avoid saying
negative things about people, because this may be
appropriate on occasion. What critical thinking
does want to avoid is the logical error of
confusing statements about people with statements
about issues. In other words it may well be that
someone deserves negative reports, but unless
that person is the thing being considered, those
negative reports do not substitute for relevant
premises.
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Ad Hominem FallaciesInconsistency and Double
Standard
The Inconsistency ad hominem shows up in the
common problem of "Do as I say, not as I do."
The fact that people may not be living up totheir
own ideals or not following their own advice does
not automatically negate the statements, since
judgment of credibility is mostly a separate
issue from evaluating arguments for or against an
idea, unless major support or the only support
for a statement is the credibility of the person
making the statement. Using different standards
for specific situations (as exceptions) may be
appropriate in some cases, but only if a separate
argument for doing that satisfies the burden of
proof.
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Ad Hominem FallaciesCircumstantial -- Positive
or Negative
A circumstantial ad hominem occurs when a
person's job or social position is used as a
premise in an argument for or against some
statement. Critical thinking takes the position
that statements are supported by relevant
premises and that is all. If people of a
particular profession or social class happen
generally to share a viewpoint, that argues
neither for nor against whether one should accept
that position. Generally, there are reasons that
lead to the shared position, and this is where
the focus of analysis should be. The question is
whether those reasons sufficiently support the
statement to justify its acceptance for the
people who either already accept it or are
considering accepting it.
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Ad Hominem FallaciesPoisoning the Well
This problem occurs when someone's statements are
preceded by negative assertions about that
person, thus predisposing the audience in a
negative way. The problem of poisoning the well
is not strictly logical, but it is still a
critical thinking issue because it is a way of
shaping perceptions. Changing what is perceived
clearly could change the truth value of intended
premises and also could change how statements are
interpreted.
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Ad Hominem FallaciesGenetic Fallacy
The genetic fallacy occurs when a statement or
set of statements is evaluated by the irrelevant
criterion of origin. Whether an individual or
group is favorably regarded or not, statements
and positions known to be associated with that
individual or group do not change their truth
value because someone else happened to accept
them. There are relevant reasons to accept or
reject a statement. These are the proper focus
of attention.
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Ad Hominem FallaciesFavoritism
Favoritism substitutes a positive feeling for an
individual or group for factual statements that
support some idea or position that is supposed to
be decided fairly. This problem may involve
application of a double standard (and so be
basically indistinguishable from it) or there may
be no pretense of applying a reasonable standard
at all. So favoritism may be concealed or openly
capricious it is the same error either way. This
is not to say that people can't do things for
others just because they like them. It's when
fairness is expected and not delivered that the
problem arises.
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Ad Hominem FallaciesTu Quoque (...and you too...)
Some failures of critical thinking are simply
annoying. The "tu quoque" fallacy is a prime
example. This problem occurs when an accusation
is made and the individual being accused levels
the same accusation at the accuser. It is
certainly possible that someone being accused of
being unreasonable is actually being unreasonble,
for example, but if that person then responds not
with logic or a demonstration of reasonableness,
but levels the same accusation of
unreasonableness, the original point is almost
automatically made.
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Ad Hominem FallaciesAbout persons instead of
premises
ABOUT CREDIBILITY... Characteristics of the
person are not irrelevant when credibility of the
source is an important factor in determining
whether a claim will be accepted. The main point
about Ad Hominem arguments is that they attempt
to substitute statements about a person (usually
negative) for relevant premises supporting a
conclusion or position.