Logical fallacies(defined)

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Chapter 3: Analyzing Arguments
Define “Argument”:
On what is the “Rogerian” model of argumentation based? What is the goal?
Claims:________________________________________________________________________

Of fact:

Of value:

Of policy:
Thesis statements:
_____________________________________________________________________

“closed thesis”:

“open thesis”:

“counterargument thesis”:
* When presenting evidence to support your claim and prove your thesis, make certain that
your evidence is ________________, _______________________, and ___________________.
Logical fallacies(defined):
Appeal to
ignorance
(lack of
knowledge or
evidence
Appeal to
irrational fears
Definition
--Whatever has not been proven false must
be true.
--Whatever has not been proven true must
be false
Example
No one can prove that the Loch Monster
does not exist; therefore, the Loch Ness
monster exists.
--Exploiting human fears to make an
argument.
Because of a few isolated cases of Mad
Cow Disease, cattle ranchers should test
each cow every month.
Appeal to pity
--Pathos used to mask a weak argument
If a student is failing a class because of
absences, failure to makeup work, and low
grades, (s)he might use the argument that a
failing grade would prevent graduation.
Appeal to
prejudice/ Ad
populum
--A writer appeals to a preexisting positive
or negative prejudice
Using the American flag on a book cover or
a bumper sticker to appeal to a person’s
patriotism
Ad Hominem /
Pro Hominem
--Criticizes
Calling someone a hypocrite rather than
focusing on the argument
… praising someone for what he has done
even if it has no bearing on argument
--Praises
Guilt by
Association
--Seeking to discredit an opponent by
associating the opponent with some
unpopular person, group, or idea.
Politics (again!): Political candidate said
she had dabbled in witchcraft at one time.
Calling opponents “free-spending liberals”
or “hard-right conservatives”.
Begging the
question
--Assumes that parts (or all) of what the
person claims to be proving are proven
facts.
--Taking for granted something that really
needs to be proved
He is an honest person so he would never
cheat on a test.
Band Wagon
Appeals
--“to the crowd”
--A misconception that a widespread
occurrence of something is assumed to
make an idea true or right
Since the parents of your friends allow
their children to stay out until 2 a.m., your
parents should let you stay out until 2, also.
Either/Or
Reasoning
(false
dichotomy)
--
The possession of firearms should be
banned.
OR
The possession of firearms should be
completely legal and unregulated.
Hasty
generalization
--
All teenagers should have a curfew of
midnight since two teens committed
crimes, both after midnight.
Non-sequitur
--“it does not follow”
--An inference or conclusion that does not
follow established premises or evidence
“He is the most popular student in school.
He should be president of the student
government.”
Free all political prisoners. (are any guilty of
actual crimes, like blowing up a building)
pedantry
Post hoc, ergo
propter hoc
propaganda
Argument from
authority
Slippery slope
--A display of narrow-minded and trivial
scholarship
--An arbitrary adherence to rules and forms
You may know tons about the rules of
grammar, but can you organize your
thoughts into good essays
--“after this, therefore because of this”
--Assuming that an event that precedes
another is the cause of the second one
I have been having so much bad luck lately
because I broke a mirror.
Political campaigns—Vote for me again
because the economy has improved
--Writing or images that seek to persuade
through __________ appeal rather than
through logical proof
Written or visual texts that describe or
depict using highly connotative words or
images without justification
--Uses a famous person to tempt the
audience to agree with what you are saying
Did people vote for Obama because Oprah
supported him?
--Suggests dire consequences from
relatively minor causes
“give them an inch and they’ll take a mile”
If we do away with a dress code, some
people will come to school naked!
Straw person
argument
--
Students who want to eliminate the school
uniform are exhibitionists who want to
show off bare midriffs.
--Attempts to appeal to the hearts of
readers so they forget their minds
The assignment that I gave you last night
was much too long, but just think how
pleased your parents and I will be when
you score a 5 on the AP exam. Think about
the pride you will feel when tears of joy
stream down our faces.
Red herring
--
My opponent talks about the poor quality
of military intelligence, but this is a time for
decisiveness, not for weakness.
Scare tactics
--Attempts to frighten readers into
agreeing with the speaker
Stem cell research will bring an end to
ethical uses of technology and could lead to
creating superraces—the Nazi dream of an
Aryan Nation will ensue!
Sentimental
appeals
Dogmatism
-- Does not allow for discussion because the
speaker presumes that his or her beliefs are
beyond question; essentially, the “logic”
runs thusly: I’m correct because I’m correct
Oversimplificati
on
--Asserting a simple answer for a complex
problem
The solution to gang violence in schools is
to require students to wear uniforms—
problem solved!
Equivocation
--Telling parts of the truth, while
deliberately hiding the entire truth—lying
by omission
Telling parts of the truth, while deliberately
hiding the entire truth—lying by omission
Faulty analogy
--
“The President hit a home run with his
labor bill.”—uses a faulty baseball
analogy—the President does not play
against Congress
Circular
Reasoning
--
“You can’t give me a C; I’m an A student!”
Specific types of evidence:

“First Hand Evidence”:
o
Personal experience
o Anecdote:
o Current Events

“Second-Hand Evidence”:
o Historical information:
o Expert opinion:
o Quantitative Evidence:
I’m correct because I’m correct
Shaping the Argument: Classical Oration

Introduction (exordium):

Narration (narration):

Confirmation (confirmation):

Refutation (refutation):

Conclusion (peroration):
Types of Reasoning:

Induction “to lead in”:
o Example:

Deduction “to lead down or from”:
o Example:
o Syllogism:
Major premise:
Major premise:
Minor premise:
Minor premise:
Conclusion:
Conclusion:
Major premise:
Major premise:
Minor premise:
Minor premise:
Conclusion:
Conclusion:
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