Which among the following are contrary propositions? A. All poets are dreamers…
2024
Which among the following are contrary propositions?
A. All poets are dreamers
B. Some poets are dreamers
C. Some poets are not dreamers
D. No squares are circles
E. No poets are dreamers
Choose the correct answer from the options given below:
- A.
D and E Only
- B.
C and D Only
- C.
B and D Only
- D.
A and E Only
Attempted by 74 students.
Show answer & explanation
Correct answer: D
Answer: All poets are dreamers and No poets are dreamers are contrary propositions.
Definition: Contrary propositions are a universal affirmative and a universal negative that have the same subject and predicate. They cannot both be true, but they can both be false.
Why the correct pair is contrary: "All poets are dreamers" (universal affirmative) and "No poets are dreamers" (universal negative) share the same subject and predicate and are of the A and E forms, so they are contraries.
Why the other statements are not contraries: particular statements like "Some poets are dreamers" and "Some poets are not dreamers" are particular affirmatives and negatives (I and O forms) and form a subcontrary relation, not a contrary one. A particular and a universal about different terms (for example any statement about squares and circles paired with a statement about poets and dreamers) are not contraries because contraries require the same subject and predicate.
Additional note: Contradictory pairs are A vs O and E vs I. For example, "All poets are dreamers" contradicts "Some poets are not dreamers", and "No poets are dreamers" contradicts "Some poets are dreamers."