Validity and Strength

Question 1

Is this argument valid, strong, or weak?

George Bush ruined the economy of the USA. He tried to rollback civil rights. He started two wars, at least one of which is a disaster. He was a terrible president.

Answer 1

Strong

Question 2

Is this argument valid, strong, or weak?

Smoking is disgusting. It makes your breath smell horrible. Kissing someone who smokes makes you want to vomit. Besides, it will kill you!

Answer 2

Strong

Question 3

Is this argument valid or invalid?

If either of us goes to the grocery store, then there will be food for dinner tonight. But if neither of us goes, then there won’t. I know that Jim didn’t go to the grocery store today, so if I want dinner tonight, I’d better head off to the grocery store.

Answer 3

Valid

Question 4

Is this argument valid, strong, or weak?

You should buy Skippy peanut butter. It’s very good peanut butter. It’s the kind that Celine Dion eats.

Answer 4

Weak

Question 5

Is this argument valid, strong, or weak?

When we arrive in class, our names get written on the attendance list, but not if we’re late. My name is on the list, so either I was on time, or I was early.

Answer 5

Valid

Question 6

Is this argument valid, strong, or weak?

Harper is not a god. Harper is human. No human is a god.

Answer 6

Valid

Question 7

Is this argument valid or invalid?

He took his bike to work today, so his job must be easy.

Answer 7

Invalid

Question 8

Is this argument valid or invalid?

All people who speak English can read English. Jake speaks English, so he must be able to read English, too.

Answer 8

Valid

Question 9

Is this argument valid, strong, or weak?

60% of Canadians play hockey. Jane is Canadian, thus she plays hockey.

Answer 9

Strong

Question 10

Is this argument valid or invalid?

I will go to bed early and get some sleep. When I get sleep, I feel better in the morning. Tomorrow, I will feel better.

Answer 10

Valid

Question 11

Is this argument valid, strong, or weak?

Man-made artifacts are complex, have functions and are designed. Natural beings, such as animals, are complex and have functions. Therefore, natural beings must also have been designed.

Answer 11

Weak

Question 12

Is this argument valid, strong, or weak?

All the ravens I’ve seen up to now have been black, so the next raven that I see will be black.

Answer 12

Strong or Weak

Depends on how many ravens they have seen!

Question 13

Is this argument valid, strong, or weak?

Every day this month the postman has come at 8:30 AM, so the postman will come at 8:30 AM today.

Answer 13

Strong

Question 14

Is this argument valid, strong, or weak?

Sheep are the dumbest of animals. If one of them walks off a cliff, the others will follow. And if they get rolled on their backs, they cannot stand up.

Answer 14

Weak

Question 15

Is this argument valid, strong, or weak?

If she’s a doctor, then she’ll be able to cure me; but she wasn’t able to cure me so clearly she isn’t a doctor.

Answer 15

Valid

Question 16

Is this argument valid, strong, or weak?

Cars cause thousands of deaths each year. Cars are more dangerous than planes. Cars are ruining the environment. It’s time to ban cars.

Answer 16

Weak

Question 17

Is this argument valid, strong, or weak?

He’s married, so he is not a bachelor.

Answer 17

Valid

Question 18

Is this argument valid, strong, or weak?

Binky told me that the ladies that work in the cafeteria spit in the soup. I’m never going to eat soup at that cafeteria again.

Answer 18

Weak

Question 19

Is this argument valid, strong, or weak?

Computers are made of silicon, and they can only follow instructions. Therefore, they will never be truly intelligent.

Answer 19

Weak

Question 20

Is this argument valid, strong, or weak?

He took his bike to work today, so his job must be easy.

Answer 20

Weak

Question 21

Is this argument valid, strong, or weak?

If the cigarette is not put out, the couch will catch fire. Sam’s cigarette will not be put out tonight, so there will be a fire.

Answer 21

Valid

Question 22

Is this argument valid, strong, or weak?

The University of Guelph was ranked as the worst comprehensive university in Canada by MacLean’s magazine. Thus, it’s probably not a very good idea for you to attend the University of Guelph.

Answer 22

Strong

Question 23

Is this argument valid, strong, or weak?

He’s likely a spy. He has a secret compartment in his briefcase and spies usually have secret compartments in their briefcases.

Answer 23

Weak

Question 24

Is this argument valid, strong, or weak?

Hi Tara, I’m on my way to school. I left 5 minutes later than usual. Traffic is heavy and I need to stop for coffee, so I might be late for class. Ciao.

Answer 24

Strong

Question 25

Is this argument valid, strong, or weak?

Every Vancouver Canucks fan rioted when they lost the final. Vilma is a Canucks fan, and an opera singer. She rioted.

Answer 25

Valid

Question 26

Is this argument valid, strong, or weak?

All the coins in my pocket are silver. Therefore, if I were to put this penny in my pocket, it would be silver too.

Answer 26

Weak

Question 27

Is this argument valid, strong, or weak?

The Toronto Maple Leafs have the best hockey players in the NHL. Unless something goes wrong, they’re virtually guaranteed to win the Stanley Cup.

Answer 27

Strong