PhB Bachelor of Philosophy Logic and Argumentation

Question 1

A deductively valid argument is one in which:

Accepted Answer

If the premises are true, the conclusion must be true

Answer

Validity is a structural property: a valid argument cannot have true premises and a false conclusion—the conclusion is guaranteed by the premises.

Question 2

A sound argument is one that is:

Accepted Answer

Valid and has all true premises

Answer

Soundness combines validity (correct logical form) with truth (all premises are actually true), guaranteeing a true conclusion.

Question 3

The fallacy of affirming the consequent is committed when someone argues:

Accepted Answer

If P then Q; Q; therefore P

Answer

Affirming the consequent ('If P then Q; Q; therefore P') is invalid because Q may be true for reasons unrelated to P.

Question 4

Modus ponens is the valid argument form:

Accepted Answer

If P then Q; P; therefore Q

Answer

Modus ponens ('mode of putting') is the foundational deductive rule: given the conditional and its antecedent, we validly infer the consequent.

Question 5

An ad hominem fallacy occurs when:

Accepted Answer

An argument attacks the person making a claim rather than addressing the claim itself

Answer

Ad hominem ('against the person') dismisses an argument by attacking the character or motives of the arguer rather than the argument's content.

PhB Bachelor of Philosophy Practice Test