Week 2 Quiz

In this course, what does it mean for a deductive argument to be valid?

Select one.

• Its premises and its conclusion are all in fact true, as written
• Its conclusion is in fact true
• Its conclusion cannot be false if its premises are true
• Most people who hear it would accept it

In this course, what does it mean for a deductive argument to be sound?

Select one.

• It is valid and all its premises are in fact true
• Its premises make its conclusion probable, without a guarantee
• It is valid, whatever its premises say
• Its conclusion is one most people find plausible

Argument 2 of Dataset B, the argument set (illustrative), reads: "If the mind is the brain, then mental states have locations. Mental states have no locations. So the mind is not the brain." Which form does it have?

Select one.

• Modus ponens
• Denying the antecedent
• The invalid categorical pattern
• Denying the consequent

Argument 6 of Dataset B, the argument set (illustrative), reads: "If the universe was designed, it shows order. The universe was not designed. So it shows no order." Which judgment does the course key?

Select one.

• Valid, because it denies the consequent
• Invalid, because it denies the antecedent
• Valid, because it is modus ponens
• Invalid, because its conclusion is false

Which statements describe the barber puzzle, this week's thought experiment, as the course teaches it? Select all that apply.

Select every option that applies.

• It is a standard logic puzzle usually associated with Bertrand Russell
• It is worked as a reductio: assuming such a barber exists leads to a contradiction
• It shows that the barber must shave himself every morning
• It comes from Plato's Republic, as a story Socrates tells

An argument has the form "every A is B; this C is B; so this C is A," and its conclusion happens to be true. What follows?

Select one.

• It is valid, because its conclusion is true
• It is sound, because its conclusion is true
• It is invalid, because the form allows true premises with a false conclusion
• It is invalid, because its conclusion must be false

True or false: one genuine counterexample is enough to refute a claim about every member of a group.

True or false.

• True
• False

A commuter says, "The bus on this route has run late on every trip I have taken, so the next one will run late too." Which description fits this argument best?

Select one.

• A valid deductive argument with true premises
• An inductive argument, judged by its strength
• A sound argument, because the premise is true
• An invalid deductive argument with a false conclusion

A friend defines a game as "an activity with a winner." Another friend points out that two people tossing a ball back and forth are playing a game that has no winner. In the Socratic habit the course began with, what is the second friend doing?

Select one.

• Restating the definition in plainer words
• Appealing to an authority on games
• Agreeing with the definition by adding an example
• Testing the definition with a case it gets wrong

How does philosophy, as this course describes it, examine fundamental questions?

Select one.

• By careful argument rather than by appeal to authority alone
• By surveying what most people already believe
• By accepting the views of the most famous thinkers of the past
• By collecting opinions without judging the reasons