1. Thomas Elder attack on social welfare should not be taken seriously. He is said to have been a degenerate.
2. You will get pregnant if you have sex. Sally had sex once, and now she is pregnant.
3. Your honor, the defendant must be guilty because no one can prove his innocence.
4. Rare taste: you either have taste or you don't.
5. Men are all alike: selfish creatures who spend every weekend glued to a television tube.
6. I am sure that you will agree that we should all work together to increase the profit of this company. Anyone not agreeing with this policy will be fired immediately.
7. Everyone believes that Lander University is improving its academic programs yearly; therefore, I conclude that Lander will be a much higher rated school several years from now.
8. Theodore H. Teabody, the great historian, says that H. Copi's book is the best logic book in the world. I believe him since the word of such a great man shouldn't be disputed.
Deductive or inductive?
deductive inductive
indicator words
|
|
| necessarily | probably/improbably |
| certainly | plausible/implausible |
| absolutely | likely/unlikely |
| definitely | reasonable to conclude |
1. The sum of the interior angles of any triangle is 180°. In triangle #1, angle A is 30°, angle B is 90°. Therefore, angle C is 60°.
2. If I get an A, then I will pass this course. Odds are, I will make a B. So, I probably won't pass this course.
3. The platypus is not a mammal because no mammal lays eggs, and the female platypus does.
4. The last time I ate here, the shrimp dish I ordered was disgusting. It must be the case that this restaurant buys lousy seafood.
5. The sign on the candy machine reads "Out of Order." The candy machine must be broken.
6. All guitar players are musicians, and some guitar players are astronauts. It follows that some musicians are astronauts.
7. Irene likes either coffee or tea in the morning. But she doesn't like tea. Therefore Irene likes coffee in the morning.
8. These mushrooms have a very similar appearance to the ones growing in the garden. The ones in the garden are edible. The conclusion is therefore warranted that these mushrooms are edible.
9. Most birds can fly and a penguin is a bird. So, penguins most probably can fly.
______________
Valid or invalid?
1. If it rained, the streets are wet. The streets are wet, so it must have rained.
2. If Richard Roe is willing to testify then he's innocent. He's not willing to testify therefore he's not innocent.
3. If Bogotá is north of New Orleans and New Orleans is north of Mexico City, then Bogota is north of Mexico City.
Strong or weak?
4. Every day you've lived has been followed by another day in which you've been alive. Therefore, everyday you ever will live will be followed by another day in which you are alive.
5. Nobel prize-winning biologist Herbert Ralls says that chlorinated hydrocarbons in our water supply constitute a major threat to the public health. Since no scientists disagree with him on this point. Accordingly, we conclude that the presence of these chemicals is a threat.
6. Every day you've ever lived has been a day before tomorrow, so, every day you will ever live will be a day before tomorrow.
No comments:
Post a Comment