Solutions to Practice Exam 3B

1. Hypothetical syllogism and modus tollens.

2. In a hasty generalization, an arguer draws a conclusion about all members of a group based on a few members of the group that are not typical of the entire group.

Example: "My car got into an accident today. I will never drive a car again; they all get into accidents."

A weak analogy is the use of an inappropriate analogy to support a conclusion.

Example: "Jupiter and Jumbo Jets have names that begin with the letter 'J'. They are also very big. John's name begins with the letter 'J'. So John must also be very big."

3. If there is good reason to suppose that the individual appealed to is in fact an authority figure in the area.

4. True. The fallacy is one in which the arguer distorts his opponent's argument and attempts to defeat this distorted version.

5. It wouldn't be fallacy if the members of the group upon which the arguer bases her generalization are in fact typical of the entire group.

6. False dichotomy. Surely there are more options than this. She might be asked out by a more handsome lad and be happy.

7. Strawman. Ted Nugent probably isn't arguing that deer hunting is OK because deer's don't mind being killed.

8. Ad hominem abusive. The arguer doesn't respond to Jones' argument, but instead insults Jones.

9. False cause. The arguer mistakes a correlation (between pot smoking and heroine use) for a causal relationship. It is obvious that pot smoking doesn't cause heroine use. There are plenty of pot smokers who don't use heroin.

10. Two readings:

Reading A: no fallacy, since this isn't even an argument.

Reading B: slippery slope. The argument is that we shouldn't allow the government to prohibit cigarettes since this would lead to a chain of events with unpleasant consequences.

11. No fallacy. The arguer is giving a counterexample to the generalization that all clones don't work well.

12. Ad hominem circumstantial. The arguer attempts to defeat Jones' argument by pointing out circumstances (being the owner) that may have led Jones to adopt that position.

13. Weak analogy. There isn't a strong enough analogy between being homosexual and being a great artist and writer, to justify the conclusion. (Some homosexuals are great artists and some aren't, just like some heterosexuals are great artists and some aren't.)

14. false cause. The arguer assumes that whiskey is the cause of Lincoln's success.

15. hasty generalization. Both sentences are very likely the result of just observing a few New Yorkers and Californians who aren't representative of these entire groups.

16. weak analogy. The case of guns is different from that of scalpels and rocks, in that guns can be dangerous and lead to crimes even in the absence of hardcore criminals. (e.g., the child who found his father's gun in a closet and started playing with it and shot his little brother. In a case like this, one could argue that the very presence of the gun is really what is to blame.)

17. ad populum. Arguer appeals to the majority to get his point across.

18. appeal to force. The harmful circumstances (no tuition payments) don't support the conclusion that it would be better to major in business.

19. Two readings.

a. no fallacy, since this isn't even an argument against Marshall.

b. ad hominem circumstantial. The argument is that we shouldn't buy Marshall's argument because of the circumstances that have led Marshall to give that argument. (This reading would be stretching things a bit, since there's no mention that we should disagree with Marshall.)

20. false authority. Though pediatricians are well-versed in the medical aspects of childbirth, we have no good reason to assume that they are all authorities on the philosophical implications of childbirth.

21.

1. (x)( Sx -> ~Wx) -> (x) (Sx -> ~Hx)
2. ~(Ex)(Sx & Wx) -> ~(Ex)(Sx & Hx) 1, CQN
3. (Ex)(Sx & Hx) -> (Ex)(Sx & Wx) 2 CONT

22.