1. C OMMON L OGICAL F ALLACIES Flawed Arguments

2. LOGICAL FALLACIES… Flaws in an argument Often subtle Learning to recognize these will: Strengthen your own arguments Help you critique other’s arguments The word “fallacy” may derive from the Latin word fallere meaning, “to deceive, to trip, to lead into error or to trick.” The word may also derive from the Greek phelos, meaning “deceitful.”

3. E RRORS IN L OGIC A fallacy is an error of reasoning. These are flawed statements that often sound true. Logical fallacies are often used to strengthen an argument, but if the reader detects them the argument can backfire, and damage the writer’s credibility; fallacies are defects that weaken arguments. Fallacious arguments are very, very common and can be quite persuasive, at least to the causal reader or listener. You can find dozens of examples of fallacious reasoning in newspapers, advertisements, and other sources.

4. A D HOC ARGUMENT You call something ad hoc when it's introduced for a particular purpose, instead of for some general, antecedently motivated reason. So, for instance, an ad hoc decision is a decision you make when there's no general rule or precedent telling you what to do. For instance, suppose you analyze "bird" as "any creature that can fly." I then cite mosquitoes as a counter-example. They can fly, but they aren't birds. Now, you might fix up your analysis as follows: A bird is any creature that can fly, and which is not a mosquito. This would be an ad hoc response to my counter-example. Alternatively, you might fix up your analysis as follows: A bird is any creature that can fly, and which has a backbone. This would be an independently motivated, and more appropriate, response to my counter- example. (Of course, someone may discover counter-examples even to this revised analysis.)

5. H ASTY G ENERALIZATION A generalization based on insufficient or unrepresented evidence Deaths from drug overdoses in Metropolis have doubled over the last three years. Therefore, more Americans than ever are dying from drug abuse. One student is arrested for drugs and suddenly all students in that school are called druggies.

6. B ANDWAGON A PPEAL ( A D P OPULUM ) A claim that an idea should be accepted because a large number of people favor it or believe it to be true. “All my friends have tattoos covering their left arms and right ankles. There is nothing wrong with body art, Mom!” “It must be cool because everyone is doing it…”

7. N ON S EQUITUR (D OES N OT F OLLOW ) A conclusion that does not follow logically from preceding statements. Or the train of thought jumps the tracks at some point. Mary loves children, so she will make an excellent school teacher. (This support alone does not follow or is Non- Sequitor—If Mary is a murderer, or has a 50 IQ, she will not make a good teacher no matter how much she loves kids.) No one should grill their steaks. Cows don’t like smoke. (This does not follow because it does not make sense. The cows are dead. They are steaks.)

8. F ALSE A NALOGY /W EAK A NALOGY The assumption that because two things are alike in some respects, they are alike in others. If we put humans on the moon, we should be able to find a cure for the common cold! IF teachers can use the phones and drink coffee in school, students should be able to also! If dad stays up until midnight, then I should be able to stay up, too!

9. A PPEAL TO P ITY Definition : The appeal to pity takes place when an arguer tries to get people to accept a conclusion by making them feel sorry for someone. Example : "I know the exam is graded based on performance, but you should give me an A. My cat has been sick, my car broke down, and I've had a cold, so it was really hard for me to study!" The conclusion here is "You should give me an A." But the criteria for getting an A have to do with learning and applying the material from the course; the principle the arguer wants us to accept (people who have a hard week deserve A's) is clearly unacceptable. Example : "It's wrong to tax corporations--think of all the money they give to charity, and of the costs they already pay to run their businesses!"

10. “EITHER… OR” FALLACY F ALSE D ICHOTOMY The suggestion that only two alternatives exist when in fact there are more. Either learn how to program a computer, or you won’ “Franklin High School is in bad shape. Either we tear it down and put up a new building, or we continue to risk students' safety. Obviously we shouldn't risk anyone's safety, so we must tear the building down.”

11. F ALSE C AUSE ( P OST H OC, C OINCIDENCE VS. C AUSALITY ) The assumption that because one event follows another, the first is the cause of the second. Every time I wear my blue sweater, it snows. OMG, MY BLUE SWEATER CAUSES SNOW!!!

12. C IRCULAR R EASONING / B EGGING THE Q UESTION An argument in which the writer, instead of applying evidence simply restates the point in other language. Santa Claus exists. How do you know? Daddy said so. How does your dad know? He just does. Chicken nuggets are good. Why are they good? Because they are tasty. Why are they tasty? Because they are good!

13. FALSE AUTHORITY The person presenting the argument is an authority, but not on the subject at hand. Three types: Self Proof—”Because I said so” Spokesperson—”Because famous person says so” Too much credit—”Because they are good at one thing, they know all things” I have a degree in Medicine and I am here to tell you the economy is about to FAIL!

14. ARGUMENT TO THE PERSON ( AD HOMINEM) An attack on the person proposing an argument rather than on the argument itself. Senator Jones was a conscientious objector during the Vietnam War, so his proposal to limit military spending has no merit. Why are you trying to show me how to organize my notes? You cannot even drive, silly girl!

15. R ED H ERRING An argument that focuses on an irrelevant issue to detract attention from the real issue. A Red Herring is literally a SMELLY FISH. You basically say, “My back is against the wall. I cannot win this argument. HERE IS AN AWFUL SMELLY FISH TO DISTRACT YOU! Mom, I know I have ISS for tardies but at least I do take care of our car!

16. F ALSE PREMISE IN A SYLLOGISM A false premise is an incorrect proposition that forms the basis of an argument or syllogism. Since the premise (proposition, or assumption) is not correct, the conclusion drawn may be in error..syllogism For example, consider this syllogism, which involves an obvious false premise: If the streets are wet, it has rained recently. (premise) The streets are wet. (premise) Therefore it has rained recently. (conclusion) This argument is logically valid, but quite demonstrably wrong, because its first premise is false - one could hose down the streets, the local river could have flooded, etc.

17. SLIPPERY SLOPE Like a muddy hill, if we go down this slope we will fall If we allow one thing/a whole slew of other, negative events will occur as a result If we allow students to have i-pods, pretty soon they will have entire systems out in class and all over the school. If we pass this health care bill eventually the government will take over the decision-making from patients and doctors

18. STRAW MAN The person attacks an argument which is different from, and usually weaker than, the opposition's best argument. Setting up a fake version of something or someone that is easy for others to not like. Ex. Katie, my shih-tzu, isn’t really hungry; she just wants us to get up all the time and cater to her every whim! People who think cell phones should be banned from campus have no respect for the rights of teens. They treat them as babies. That's wrong. Teen must have the right to have cell phones at school.

19. F ALLACIES OF A MBIGUITY - These errors occur with ambiguous (unclear) words or phrases. - Division: what is true of the whole, or the group, must be true of the parts, or the members - “I have so much homework to do, I won’t even try to get started.” In a philosophical discussion, you should call a term "ambiguous" when and only when the expression has more than one acceptable meaning. For instance, "bank" is ambiguous (river bank, Bank of Boston). Also, sentences can be ambiguous, as in "Flying planes can be dangerous." Is it the activity of flying which is dangerous, or is it the planes which are dangerous?

20. C ARD S TACKING Only tells part of the story – the favorable part that helps your product or cause – when other facts exist that hurt it, in other words, Stacking the deck in your favor omitting relevant facts that hurt you McDonald’s has served over 99 billion hamburgers. (That does not tell you that the burgers are full of calories and not heart healthy.)

21. A CTIVITIES : 1) Write an argument using as many logical fallacies as you can 2) Find visual examples of logical fallacies from advertisements, etc.