Exercise 11

Instructions: Rewrite each of the following arguments in standard form, and say whether or not the argument is valid. (Use the flow-chart handout if necessary.) If the argument has a famous form, write the name of the form as well.

1. Trying to be happy is a sufficient condition for misery. The reason is that if you try to be happy then all you can think about is how you aren’t happy now. And if all you can think about is how you’re not happy, then clearly you’ll be miserable.

2. Having a 2.0 GPA is a necessary condition for graduation. I have a 2.0 GPA, so it follows that I will graduate.

3. Either Wyatt Earp was the best gunfighter that ever lived or he died in a hail of gunfire. Wyatt Earp did not die in a hail of gunfire. Therefore he’s the best gunfighter that ever lived.

4. My car will start only if I am favored by the gods. I am indeed favored by the gods. Therefore my car will start.

5. My car did not start this morning. Since my car will start only if I am favored by the gods, it must be the case that the gods do not favor me.

6. It is easy to see that America is being run by aliens and/or the freemasons. If prescriptions of Ritalin have increased in the last five years, then it’s being run by aliens. And if education has done nothing but prepare our kids for servitude then it’s being run by the freemasons. It’s certainly the case that either kids are taking more Ritalin or the education system is a failure, so there you have it.

7. Al Gore says the whole world is going to look like the Rouge River plant if we do nothing, but Al Gore is a giant nerd. It follows that Al Gore is a giant nerd.

8. If you eat your cake, then you will not be able to enjoy looking at it, but if you do not eat your cake, then you will not be able to enjoy tasting it. Therefore, one can enjoy either eating cake or looking at cake, but not both.

9. The next president we elect needs to be strong on both domestic and on international issues. This is because if he or she is strong only on domestic issues, then foreign relations will suffer. The economy will suffer if he or she is strong only on international issues. We can’t afford to suffer in either domestic issues or foreign relations, so the next president needs to be great at both.

10. The government bailout of Bear Sterns was responsible just in case it was necessary to avert a national slide into economic depression. It was necessary, so we have to agree that the government’s actions were responsible.

10. Having at least a 2.0 GPA is a necessary condition for graduation at Marygrove College.

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