Examine the following claims about traditional categorical logic: A. An…
2024
Examine the following claims about traditional categorical logic:
A. An inference is immediate when its conclusion is drawn from more than one premise.
B. Two propositions are contradictories when one is the denial of the other.
C. Subcontraries cannot both be true, although they may both be false.
D. Negative categorical propositions distribute their predicate terms.
E. The quality of a categorical proposition determines whether its subject term is distributed.
Choose the combination containing only the correct claims.
Answer: C. B and D only — ConceptTraditional categorical logic distinguishes relations on the square of opposition and the distribution of terms. An immediate inference draws a…
- A.
A and C only
- B.
B and E only
- C.
B and D only
- D.
A, C and D only
Show answer & explanation
Correct answer: C
Concept
Traditional categorical logic distinguishes relations on the square of opposition and the distribution of terms. An immediate inference draws a conclusion from one premise, while a mediate inference uses more than one premise.
Contradictories are exact denials and therefore cannot share a truth value. Subcontraries may both be true but cannot both be false. In categorical propositions, quantity governs subject distribution, whereas negative quality governs predicate distribution.
Application
Claim | Rule applied | Assessment |
|---|---|---|
A | An immediate inference uses one premise, not more than one. | False |
B | Contradictory propositions deny one another and have opposite truth values. | True |
C | Subcontraries can both be true, but they cannot both be false. | False |
D | The predicate is distributed in both negative forms, E and O. | True |
E | Quantity, not quality, determines subject distribution. | False |
Cross-check and contrast
A and C only contains two false claims.
B and E only combines a true claim with a false claim.
B and D only contains exactly the two true claims.
A, C and D only includes two false claims along with one true claim.
Therefore, the correct combination is B and D only.