Accept every statement below as true, whatever the real world says. Which of the conclusions must then be true?
Statements:
1. All chairs are bungalows.
2. All tables are bungalows.
Conclusions:
I. Some chairs are tables.
II. Some tables are chairs.
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Neither conclusion I nor conclusion II follows
A conclusion follows only if it is true in every diagram that fits the statements. One diagram in which a conclusion is false is enough to reject it.
“All chairs are bungalows”: the circle of chairs lies inside the circle of bungalows
“All tables are bungalows”: the circle of tables also lies inside the circle of bungalows; nothing is said about chairs and tables
Conclusion I: Some chairs are tables. — Does not follow. The two circles inside bungalows need not meet: in the diagram no chair is a table.
Conclusion II: Some tables are chairs. — Does not follow. This is conclusion I read the other way round, and it fails in the same diagram.