2. Common Mistakes in Weak Arguments
LOGICAL FALLACIES
Common Mistakes in Weak Arguments

3. Introduction Ad Hominem Hasty Generalization False Dilemma
Begging the Question
Post Hoc
False Analogy
Emotional Appeals
Red Herring
False Authority
Bandwagon

4. 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.

5. Most logical fallacies masquerade as reasonable statements, but they are in fact attempts to manipulate readers by reaching their emotions instead of their intellects.

6. Ad Hominem (Personal Attack)
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?

7. 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.

8. 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?

9. 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!

10. False Analogy Example can’t we find the cure for the common cold?
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.

11. Appeal to Fear
This claims that if you don’t take a certain action, something undesirable will happen as a result.
Sure, you can smoke…if you
want to get lung cancer and die!

12. 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.

13. 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.

14. 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.

15. Post Hoc Example
Since Governor Bush took office, unemployment of minorities in the state has decreased by seven percent. Governor Bush should be applauded for reducing unemployment among minorities.
Before we pat the governor on the back, the speaker must show that Bush’s policies are responsible for the decrease in unemployment. It is not enough to show the decrease came after his election.

16. Emotional Appeal
This term refers to manipulating someone by targeting their emotions or desires.
For example, the ad may make you feel happy, sad, angry, fearful, anxious, etc.

17. Red Herring
The name comes from the sport of fox hunting in which a dried herring (red in color) is dragged across the trail of the fox to throw the hounds off the scent.
Logical maybe…but unrelated. The argument uses distraction to avoid the issue.

18. Bandwagon
This fallacy attempts to persuade you by claiming that everyone else is doing it too.
Peer pressure
Be like the 2 million
other customers who have
already tried this prduct!”

19. False Authority
This fallacy either appeals to someone who is not an expert, or it uses an expert who’s area of expertise is irrelevant.
Madonna is against animal testing, so animal testing must be unethical.
Noted psychologist Dr. Frasier Crane recommends that you buy an E-Z Rest hot tub.
I read on the internet that aliens have already started overtaking human bodies, so you’d better watch out!

20. Slippery Slope
This fallacy assumes that if a certain course of action is taken, the worst will inevitably result.
“If you drink as a teenager, you will become an alcoholic as an adult.”
The possibility of this happening is certainly real, but it will not necessarily happen every time.