Take the statements below to be true, even if they differ from known facts. Which of the conclusions follow logically from them?
Statements:
1. All nurses are climbers.
2. All nurses are skaters.
Conclusions:
I. Some climbers are skaters.
II. All skaters are climbers.
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Only conclusion I follows
A conclusion follows only if it is true in every diagram that fits the statements; each class named in a statement is taken to have members.
“All nurses are climbers”: the circle of nurses lies inside the circle of climbers
“All nurses are skaters”: the circle of nurses also lies inside the circle of skaters, so climbers and skaters must meet at least where the nurses are
Conclusion I: Some climbers are skaters. — Follows. The nurses are climbers and also skaters, so at least the nurses are climbers who are skaters.
Conclusion II: All skaters are climbers. — Does not follow. Only the nurses are sure to be climbers; the other skaters may lie outside the climbers, as in the diagram.