Logical Fallacies, Ch 6, RRW

1. Logical Fallacies, Ch 6, RRW Ch. 6, Logic

2. But first, some visuals… Let’s relate these to figures of speech, and logical fallacies, if possible…

3. Visual and Audio of Debate… Hot Air: Will Perry “break the rules” to get his mojo back? posted at 3:25 pm on October 18, 2011 by Ed Morrissey The Texas governor’s team has a new strategy to get Perry more involved — and more eloquent:  ”We’re going to pay a little less attention to the rules,” says a source in the Perry camp who asked to go unnamed.  “One of the things the governor tried to do in New Hampshire [at the Bloomberg/Washington Post debate] was to live by the time limits set by organizers.  No one else did.  As a result, one could view the governor’s performance as having less to say, when in fact he was simply trying to live up to the rules of the debate.  They’ve rarely been enforced, and we’re not going to pay much attention to them.”

4. Visual and Audio of Debate… • http://www.ktrh.com/pages/Connected.html?page=3Bachmann, 0:00 – Logical fallacy? • http://www.mediaite.com/tv/mitt-romney-and-rick-perry-get-into-illegal-immigration-slapfight/Perry/Romney, 0:55-1:25 – Logical fallacy? • Will Perry’s plan work?

5. Logical Terms/Fallacies 1. Inductive logic • = Inferential logic – What can we infer / conclude based upon the evidence, facts, or information? • Example: Were dinosaurs truly the dominant life form (during Mesozoic era)? (Were they very diverse?)  Claim? • The process of induction… Grounds (evidence)  diversity of fossils (facts) • Assumption (warrant): The facts are representative, and reveal dinosaur diversity….

6. Logical Terms/Fallacies 2. Deductive logic • Major Premise: All men are mortal. • Minor Premise: Socrates is a man. • Conclusion: Socrates is mortal. • (The traditional syllogism…) • Diagram?

7. Logical Terms/Fallacies • Now, place the Socratic syllogism into the modern structure… • Claim: • Grounds: • 1. • 2. • Assumption (Warrant):The relationship of the two reasons leads, logically, to the conclusion.

8. Logical Terms/Fallacies • 3. Argument by Analogy • Cat-leash-law analogy…. • Cats are pets, just like dogs. • Cats should be required to be walked on a leash, just like dogs…. • What is overlooked? Fundamental difference in the two animals’ personalities….

9. Logical Fallacies What would be an example of a fallacy in each of the above? Take an issue such as same-sex marriage, or legalization of marijuana…. How would these 2 issues look like as argued inductively, deductively, or analogically? What are potential fallacies?

10. Logical Fallacies • Now the fallacies (listed in RRW)… (Let’s relate these to some of our examples from presentations....) 4. Hasty (faulty) generalization (or overstatement, oversimplification) • Lawyers are only interested in making money…. • Look at the grounds / assumption…. 5. Forced hypothesis (error in induction)  illogical… • Professor Redding’s students received either A’s or B’s last semester. He must be an excellent teacher. • Either (1) sufficient evidence exists; or… • (2) the evidence can be explained more sensibly by a different hypothesis. 6. Non Sequitur = Latin, “it does not follow” • Juan did well in his math class; therefore, he will certainly do well in English.

11. Logical Fallacies 7. Slippery slope • If we allow the government to register handguns, it follows that it will next register hunting rifles, and eventually eliminate all citizen ownership of guns…. Really? 8. False dilemma (either-or argument) • The Federal Reserve System must lower interest rates, or we will never pull out of this recession. 9. False analogy • A “fundamental difference” really exists but is not considered in the argument….. • The cat-leash-law argument

12. Logical Fallacies • 10.Post hoc fallacy • (Post hoc, ergo propter hoc = “after this, therefore because of this”)  Notice the chronology of this…. • We should throw out the entire city council. New members were elected, yet the city has gone into deficit spending. • (Which was first? And did one necessarily cause the other?) • 11.Begging the question • To assume part of your argument is true without supporting it is to “beg the question.” • “The fact is…” (to introduce an opinion) • “Clearly” / “Obviously” / “As we can see…” (without supporting it…)

13. Logical Fallacies • 12. Straw man • Oversimplifying (or distorting) an opponent’s argument, then attacking this oversimplified (or distorted) version. • The “straw man” cannot fight back… • “Gun control advocates simply want to take all guns away from responsible citizens and put them in the hands of criminals.” • (Really? Who claims this?) • 13. Ad hominem (“to the person”) • Attacking a person (“those self-righteous fascists!”) • Does not contribute to meaningful debate…

14. Logical Fallacies • 14. Common practice (bandwagon) • The “everyone’s doing it” fallacy…. • Also, just because the majority are doing it doesn’t make it right…. • 15. Ad populum (“to the people”) • Appealing to God, mother, apple pie, and “traditional family values” • Also, note: “red herring” = introducing a side issue, one which is supposed to divert people away from the central issues… (Do we see this today? Where?)