Testing Syllogisms for Validity 3

Rewrite the following syllogisms in standard form, and test for validity using each of the three methods:

1. Not all philosophers ski. But only skiers are snowboarders. Therefore No philosophers are snowboarders.

2. No one who is clever is president. That's because all presidents take risks and there are risk takers who are not clever.

3. The only good musician is one who plays jazz. None who play jazz are cellists. Therefore no cellists are good musicians.

4. No one except philosophers understand the world. But some who understand the world are too lazy to fix it. Therefore all philosophers are too lazy to fix the world.

5. Only Martians are green people. All green people are friendly. Therefore, Martians are friendly.

6. Some peanut growers are presidents. All presidents are Southerners. Therefore Some Southerners don't grow peanuts.

7. All Hardy novels are well-written. The only well-written novels were those written in the 19th century. Therefore all Hardy novels were written in the 19th century.

8. Some Democrats are conservative. Some Republicans are not conservative. Therefore no Democrats are Republicans.

9. Only red tomatoes are edible. Nothing which is edible is delicious. The only delicious things are red tomatoes.

10.  Snake bites are sometimes fatal. Nothing fatal is fun. Therefore snake bites are not fun.