Mensa IQ Test Mensa IQ Syllogisms and Logical Arguments 6

Question 1

Premises: No fish are mammals. Dolphins are mammals. Which MUST be true?

Accepted Answer

Dolphins are not fish

Answer

Some fish are dolphins

Answer

Dolphins are fish

Answer

All mammals are dolphins

Question 2

Argument: 'This medicine must work — my grandfather took it and lived to 95.' This commits which fallacy?

Accepted Answer

Anecdotal evidence (hasty generalisation)

Answer

Ad hominem

Answer

Straw man

Answer

Circular reasoning

Question 3

Some politicians are honest. All honest people are trustworthy. Which is valid?

Accepted Answer

Some politicians are trustworthy

Answer

All politicians are trustworthy

Answer

No politicians are trustworthy

Answer

All trustworthy people are politicians

Question 4

Argument: 'Either you're with us or you're against us.' What fallacy does this commit?

Accepted Answer

False dilemma (false dichotomy)

Answer

Ad populum

Answer

Slippery slope

Answer

Begging the question

Question 5

All S are M. All M are P. Some P are Q. Which conclusion is VALID?

Accepted Answer

All S are P

Answer

All S are Q

Answer

No S are Q

Answer

Some M are Q

Question 6

Premises: If the alarm rings, I wake up. I woke up. Therefore the alarm rang. Is this valid?

Accepted Answer

No — this is affirming the consequent

Answer

Yes — modus ponens

Answer

Yes — modus tollens

Answer

No — denying the antecedent

Question 7

All champions train hard. Mike does not train hard. Which is valid?

Accepted Answer

Mike is not a champion

Answer

Mike might be a champion

Answer

All non-trainers are champions

Answer

Training hard is sufficient to be a champion