Phil 04 – Spring 2010 Fourth Homework
Anderson
Section 03, due Friday, Mar. 19
Section 08, due Thursday, Mar. 18
Problems 1-4, do the following:
(a) Identify whether it is an argument or not. If not just write “no argument”.
(b) If it is an argument, write out each premise and the conclusion as separate lines. Clearly indicate which line is the conclusion.
(c) Indicate whether the argument is deductively valid, inductively strong or inductively weak.
1. Problem 7, p. 114
2. Problem 13, p. 115
3. Problem 14, p. 167
4. Problem 11, p. 169 Note: the background context of this passage is whether there should be an amendment prohibiting flag desecration.
Problems 5-6, determine by truth-table analysis whether the arguments are valid or invalid. Show your work.
5. P → Q 6. S → ~A
~P A
\ ~N \ ~S
Problems 7-8, Label each premise and the conclusion as A, E, I, or O, as appropriate and determine by Venn diagram whether the arguments are valid or not. Draw a clear diagram and label it appropriately.
7. All frogs are cute. No orange things are cute. Therefore no frogs are orange.
8. All illie pies are hairy. Some bluegroats are hairy. So, some bluegroats are illie pies.
9. Suppose you are debating the claim that cigarette smoking causes cancer. Which of the following assertions (or arguments), if true, would be logically relevant support for or against that point and which would be irrelevant? By logical relevance is meant the idea that if the statement were true (or the argument sound), it would have some bearing on the truth or falsity of the claim in question.
(a) If large numbers of people stop smoking, then many tobacco farmers will have to quit their farms and find some other way to make a living.
(b) Everyone has a right to smoke since this is a free country and the government has no business imposing restrictions on tobacco use.
(c) Smokers are usually heavy coffee drinkers. It may be true that cigarette smokers are more likely to develop cancer, but it’s not because they smoke , rather it is because they drink lots of coffee.
(d) My uncle Fred smoked three packs of Camels a day for fifty-three years before he died in an auto accident. An autopsy showed that he didn’t have a trace of cancer in him.
10. Which of the following, if any, are examples of enumerative induction:
(a) Sixty percent of American bachelors read Playboy.
Therefore, sixty percent of Canadian bachelors read Playboy.
(b) Sixty percent of American bachelors read Playboy.
Therefore, sixty percent of all bachelors read Playboy.
(c) Sixty percent of all bachelors read Playboy.
Therefore, sixty percent of American bachelors read Playboy.
11. A random survey was made of 1,000 callers to a drug hotline (where callers are given over-the-phone information and advice on drug use and abuse). The callers are not required to reveal their identity if they so wish. The survey was taken over a period of one year and produced the following results: 573 callers reported that they were steady users of hard drugs; 220 reported they were only “recreational” (occasional) users of hard drugs; 92 callers reported they were not drug users at all; they just wanted information; and the remainder refused to answer questions about their drug use. The takers of the survey concluded that a majority of drug users – at least among those in the calling area – are steady users of hard drugs.
(a) What is the target group (or target population) of this study?
(b) What property or characteristic of the target population did they want to know?
(c) What was the sample that they took to arrive at their conclusion?
(d) Based on that sample, what did they conclude about the target population?
(e) This is a seriously flawed study. Their conclusion should not be trusted. What is wrong with it?
12. Regarding Essay 5 in the text (486-487): “More Innocents Die When We Don’t Have Capital Punishment”. Prager grants that some innocent people are executed as long as we have the death penalty. But he argues that if killing innocent people is wrong, then to be consistent we would have to stop many very useful social activities such as auto driving, flying, construction work, etc., since these all involve the taking of innocent lives. But that would be absurd. Therefore, the abolitionist cannot condemn the death penalty for this reason at least.
Prager has made a serious error in his reasoning. What is it?