[(C ⊃ D) • ∼D] ⊃ ∼C
Which of the following propositions is a proper assumption for conditional proof to prove that the above wff is a logical truth of PL?
A) [(C ⊃ D) • ∼D] ⊃ ∼C
B) (C ⊃ D) • ∼D
C) C ⊃ D
D) C

Question

Quizplus · Accepted Answer

The proper assumption for a conditional proof to prove that the given well-formed formula (wff) is a logical truth in propositional logic (PL) is the antecedent of the conditional statement. In this case, the antecedent is "[(C ⊃ D) • ∼D]", which matches choice B. This assumption allows us to derive the consequent "∼C" through conditional proof.