LOGICAL FALLACIES
the above link gives you an introduction to the issue
Common Mistakes in Weak Arguments
Introduction: Nine Fallacies
 Emotionally Loaded Terms
 Ad Hominem
 Faulty Cause and Effect (Post Hoc ergo propter hoc )
 Either/Or Reasoning (Bifurcation)
 Hasty Generalization
 False Analogy
 Begging the Question (Circular Reasoning or Tautology )
 Non Sequitar (“It does not follow)
 Oversimplification
RHETORICAL APPEALS:
USING LOGOS, ETHOS, PATHOS
 LOGOS = LOGIC and REASON= Soundness of
facts, evidence, statistics, and reasoning; soundness of
authority’s statements outside self; well-documented
evidence
 ETHOS = Credibility and reliability of writer
him/herself; character and reputation of the author
 PATHOS = EMOTION = Appeal to needs, values,
and attitudes; uses the emotional power of language
Definition
Logical fallacies are flaws in reasoning that
lead to faulty, illogical statements. They are
unreasonable argumentative tactics named
for what has gone wrong during the
reasoning process.
Most logical fallacies masquerade as
reasonable statements, but they are in fact
attempts to manipulate readers by reaching
their emotions instead of their intellects.
Fallacy:
Emotionally Loaded Terms
Definition: Using emotionally charged words
to distract the reader from the real argument
(a type of red herring).
Example:
You slowly poison your children when you
feed them fast food.
Emotionally Loaded Arguments Offer too
Blatant an Appeal to Emotions
 Appeal to emotions manipulates people’s emotions in
order to get their attention away from an important
issue.
 You commit the fallacy of appeal to emotions when
someone’s appeal to you to accept their claim is
accepted merely because the appeal arouses your
feelings or anger, fear, grief, love, outrage, pity, pride,
sexuality, sympathy, relief, and so forth.
Ad Hominem
Latin for to the man
Directly attacks someone’s appearance, personal
habits, or character rather than focusing on the
merit of the issue at hand. The implication is that if
something is wrong with this person, whatever
he/she says must be wrong.
How can you say he’s a good musician
when he’s been in and out of rehab for
three years?
Ad Hominem – Making it Personal
Sara is divorced, so whatever relationship advice
she gives you can’t be good.
It is the suggestions, not the person who makes
them that deserve attention. Sara’s marital status
has nothing to do with the quality of her advice.
Isn’t it also possible that Sara could be married and
give awful advice?
If my husband forgot to wash his dish, I
would move out too. You did the right
thing, Carol.
Post Hoc Fallacy
Faulty cause-and-effect reasoning
Just because two events occur in close proximity does
not mean that one is necessarily related to the other.
Example: After President Clinton took office, the
economy stabilized. Obviously the Clinton
Administration’s fiscal policies were effective.
Example: A black cat crossed Babbs' path yesterday
and, sure enough, she was involved in an automobile
accident later that same afternoon.
Does the Cause Equal the Effect?
Either – Or / False Dilemma
A false dilemma asserts that a complex situation
can have only two possible outcomes and that one
of the options is necessary or preferable.
Either go to college or forget about making money.
This falsely implies that a college education is a
pre-requisite for financial success.
Was it her college education that made
Britney tons of money?
Either/Or
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Hasty Generalization
A hasty generalization is a conclusion based on
insufficient or unrepresentative evidence.
Stereotyping and Sexism are forms of this fallacy.
Take, for example common dumb blonde jokes:
Q: What do you call a blonde skeleton
in the closet?
A: Last year's hide-and-go-seek winner.
Example of a Generalization
The only redheads I know are rude.
Therefore, all redheads must have bad
manners.
If the speaker only knows two redheads, then he
has insufficient evidence to make the general
claim about all people with that hair color.
False Analogy
An analogy points out
similarities in things that
are otherwise different. A
false analogy claims
comparison when
differences outweigh
similarities. Essentially,
it’s comparing apples and
oranges!
False Analogy Example
If we can put a man on the moon, why
can’t we find the cure for the common
cold?
While both things being compared here are related to
science, there are more differences than similarities
between space and biological advancements.
False Analogy (Continued)
Begging the Question
This is a kind of circular argument where the
support only restates the claim.
Wrestling is dangerous because it is unsafe.
Jogging is fun because it is enjoyable.
Unsafe means the same thing as dangerous and
fun means the same thing as enjoyable. This
makes the reasoning circular.
Circular reasoning
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Non Sequitur (Does Not Follow)
 A conclusion that does not follow logically from
preceding statements or that is based on irrelevant data:
Mary loves children, so will make an excellent school
teacher.
Non Sequitar (continued)
Oversimplification
This fallacy occurs when a series of actual causes are
reduced to the point where there is no longer a genuine
connection between the cause and effect.
Often a result of trying not to bog a reader down with too
many details, but oversimplification can lead you down
bad roads.
For example,
– School violence has gone up and academic
performance has gone down ever since racial
segregation was banned. Therefore, segregation should
be reintroduced, resulting in school improvement.
Oversimplification
 Oversimplifying. Giving easy, smug, or pat
answers to complicated questions, sometimes by
appealing to emotion rather than logic. Examples:
“Guns don’t kill-people do” is an overly simple
but popular argument against gun control. It
sounds good but it doesn’t address the complex
problem that the availability of guns poses in our
society.
Logical Fallacies
These fallacies of argument can effectively
incite action as well as be the type of
material filling up banners, stickers, and
especially, advertisements. However, as
intellectuals we are expected to bring an
equal measure of logic and passion to our
decisions. Therefore, keep an eye out for
these fallacies as the television or computer
is likely exposing these to you right now!