1. Eng 111 Dana Frierson Fall 1998

2. Types of Reasoning (Logic) n Deductive u Inferring particular “fact” from general assumptions u General to specific n Inductive u Moving from evidence to conclusions u Specific to General

3. Deduction n Chain of reasoning involving premises and conclusion n Three part chain of reasoning: syllogism u All humans are mortal. (major premise) u Socrates is a human. (minor premise) u Socrates is mortal. (Conclusion)

4. Induction n Based on fair sample of evidence n You taste 30 green apples. n Each one is sour. n You generalize that green apples are sour.

5. Fallacious Reasoning n Error in logic n Often designed to trick or fool audience n Sometimes, used unintentionally n Avoid them in your argument

6. Common fallacies n Non Sequitur: Conclusion does not logically follow its premise u Jones will make a good senator because he is a man. n Post hoc: Claim there is a cause-effect relationship when there is not. u Superstitions

7. Common Fallacies n Allness: Imply that something is true for an entire class or group u Daughters have a special bond with their mothers. n Begging the Question: Say the same thing in different words. u Abortion is murder because it is the intentional killing of a human being.

8. Common Fallacies n Either/Or: State that there are only two alternatives u America, love it or leave it! u If you think education is expensive, try ignorance. n Faulty Authority: “authority” lacks credibility or expertise to support claim u Most commercials that use celebrities!

9. Common Fallacies-Distractions n Ad Hominem: attack the character of opponent n How dare Congressman Smith advocate population control when he has six children? n Red Herring: Divert attention by irrelevant issue n What difference does it make whether Clinton is guilty of perjury when the economy is doing so well?

10. Fallacies, Cont. n False Analogy: two cases are not sufficiently parallel. u Johnny Cochran’s analogy n Bandwagon: Appeal to people’s urge to belong u “Wouldn’t you like to be a pepper too?”

11. Fallacies, Cont. n Slippery Slope: If we take one step, it will lead to extreme u If I make an exception for you; I have to make an exception for everyone. n Loaded Question: Question will cast guilt no matter how opponent responds. u When did you stop abusing your wife?

12. Name that fallacy! n Employees are like nails. Just as nails must be hit in the head in order to make them work, so must employees. n False Analogy

13. Name that Fallacy! n Chicken soup cures colds. I ate some chicken soup and two days later, my cold disappeared. n Post Hoc

14. Name that Fallacy! n If guns are outlawed, only outlaws will have guns. n Slippery Slope

15. The Bible is true because it is inspired by God. Begging the question

16. Name that Fallacy! n All wars are not wrong. The people who say so are cowards. n Ad Hominem

17. Essay Assignment n Read Essay n As you read, note errors in reasoning. n Try to label fallacies, if you can. n Don’t be surprised when I call on you to share your discoveries!

18. Final Draft Due Tuesday!