In syllogistic reasoning, a conclusion containing the word all can follow only if
- A. at least one premise is particular
- B. both premises are universal
- C. one premise is negative
- D. both premises are negative
Explanation
A universal conclusion requires universal support, so any particular premise limits the conclusion to some. Two negative premises yield no conclusion at all, which disposes of the last option. These structural rules let many questions be answered without examining the content.
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