1. AcDv B61 Recognizing Logical Fallacies
Bakersfield College
Jessica Wojtysiak
AcDv B61 Recognizing Logical Fallacies

2. Journal Entry: Banned & Challenged Books
Think about your experience with banned and challenged books. Prior to this class, did you ever read a challenged or banned book? Did it surprise you to learn that the book had been challenged or banned? Do you support banning books? What value is there in reading books that some people find objectionable or offensive?

3. Argumentation (Persuasion)
The writer articulates an opinion about a topic
Sometimes involves using outside sources and references to other writers

4. How to Evaluate an Argument?
Rhetorical Modes
Claim
Data
Warrant

5. Watch out for Fallacies
Logical Fallacies are errors in reasoning that appear to support an argument.
They are either flawed or irrelevant to the actual argument being advanced.

6. Why do we care?
As writers and speakers, we should make an effort to avoid logical fallacies.
As readers, we should learn to identify the logical fallacies used by others.

7. Aristotle was the first to identify He identified 13
Thank you, Aristotle
Aristotle was the first to identify
He identified 13
Researchers have since expanded on that number

8. Circular reasoning
Argument assumes that the conclusion is true.
The claim is essentially stated twice
The warrant and/or data is missing

9. Circular Reasoning
“I have a right to say what I want. Therefore, you don’t get to silence me.”

10. Hasty Generalization
Definition: Making assumptions about a whole group or range of cases based upon an inadequate sample (one that is too small or atypical).

11. Hasty G Examples
My roommate said her English class is hard, and my English class is difficult, too! All English classes must be difficult!

12. Stereotypes
Stereotypes about groups of people are a common form of hasty generalization.

13. Hasty G Examples
Wealthy people are all superficial snobs who don’t earn their own money, like the Kardashians.

14. How to Avoid
Check Your Evidence
Are you relying upon a limited number of cases to make a broad conclusion?

15. Make a more modest conclusion that can be supported by your data.
Avoid HG
Make a more modest conclusion that can be supported by your data.
“Some English courses are difficult for some students.”

16. Post Hoc, Ergo Propter Hoc
The Assumption that because B came before A, B caused A. Sometimes this is true, but not always.

17. Post Hoc, Ergo Propter Hoc
Example: President Obama raised taxes. Then, the unemployment rate increased. President Obama is responsible for the rise in unemployment.

18. How to Avoid It
When making a causal claim, explain the causal process. The basis for your explanation needs to be more than simply the fact that the two events occurred in succession.

19. Fix the Previous Example
You could point to economic data showing that increased taxes causes business leaders to cut costs in order to handle the tax burden by firing people.

20. The Slippery Slope
One event or step causes a chain reaction of terrible things. Even one step in the wrong direction will send us over the brink.

21. The Slippery Slope Example
Voting to legalize homosexual marriage will lead to the legalization of marriage between people and animals.

22. Slippery Slope Example
Animal experimentation reduces our respect for life. If we don’t respect life, we will become more tolerant of war and murder, leading to the end of civilization.

23. Check the reading for chains of events.
How to Avoid It
Check the reading for chains of events.
Ensure that the chains are reasonable.

24. Appeal to Authority
We use a famous name or appeal to an authority figure in order to convince our audience that we are correct.

25. Example
Common in Ads
These pills are endorsed by Cindy Crawford as safe and effective for weight loss. They must be good.

26. George Clooney opposes the death penalty, and we should, too.
Example
George Clooney opposes the death penalty, and we should, too.

27. How to Avoid
We need to recognize that authorities may be wrong, and that even authorities can disagree.
We should never rely fully upon authority endorsement as the only reason for our position.

28. Definition: The Latin translates to mean “to the people.”
Ad Populum
Definition: The Latin translates to mean “to the people.”
This fallacy says that the mob agrees with you, or that all the cool people agree with you.

29. Atheists are immoral. Over 70 percent of Americans think so!
Examples
Atheists are immoral. Over 70 percent of Americans think so!
God must exist, because every culture recognizes the existence of some higher power.

30. Remember that what is popular is not always right.
How to Avoid
Remember that what is popular is not always right.

31. This fallacy attacks the opponent who holds a different view.
Ad hominem
This fallacy attacks the opponent who holds a different view.

32. That story was on Faux News. It can’t be true.
Example
Andrea Dworkin argues that pornography harms women. But she is a bitter and ugly person, so why should we listen to her?
That story was on Faux News. It can’t be true.

33. Focus on the argument, not the person.
How to Avoid It
Focus on the argument, not the person.

34. The Straw Person (Straw Man)
Intentionally misstating the argument of one’s opponent in order to make the opponent’s argument appear weaker.

35. Example
Feminists want to ban all pornography and punish all men who view it. Punishment is not appropriate, so the feminists are wrong.

36. How to Avoid
Be fair and thoughtful when disagreeing with others. Ensure that you understand their point of view, and the evidence used to support their perspective.

37. End?
Any Questions?

38. For Wed.
We’ll work on Fallacies Worksheet #1 in class. You’ll complete #2 on your own. The Worksheet is available through the course website.