Two Statements followed by four Conclusions are given below. You have to take the Statements to be true even if they seem to be at variance from the commonly known facts. Read all the Conclusions and then decide which of the given Conclusions logically follows/follow from the Statements, disregarding the commonly known facts : Statement-1 : All pens are books. Statement-2 : No chair is a pen. Conclusion-I : All chairs are books. Conclusion-II : Some chairs are pens. Conclusion-III : All books are chairs. Conclusion-IV : No chair is a book. Which one of the following is correct?
- (a) Only Conclusion-I
- (b) Only Conclusion-II
- (c) Both Conclusion-III and Conclusion-IV
- (d) None of the Conclusions follows ✓ UPSC's answer
Why the answer is (d)
• From Statement-1 ('All pens are books'), the set of pens is entirely contained within the set of books.
• From Statement-2 ('No chair is a pen'), the set of chairs and the set of pens are completely disjoint.
• Combining these, we know chairs are not pens, but there is no information linking chairs directly to books; chairs could be books or not, so Conclusion-I ('All chairs are books') and Conclusion-III ('All books are chairs') do not follow.
• Since no chair is a pen, Conclusion-II ('Some chairs are pens') is directly contradicted by Statement-2.
• Regarding Conclusion-IV ('No chair is a book'), while chairs are not pens, and pens are books, it is possible for a chair to be a book that is not a pen (since not all books are pens), so this conclusion does not necessarily follow.
• Therefore, none of the four conclusions logically follow from the given statements.
Why the other options are wrong
- (a) Only Conclusion-I
- Conclusion-I does not follow because there is no logical link establishing that chairs are books, only that they are not pens.
- (b) Only Conclusion-II
- Conclusion-II is false because Statement-2 explicitly states that no chair is a pen.
- (c) Both Conclusion-III and Conclusion-IV
- Conclusion-III does not follow as books are not necessarily chairs, and Conclusion-IV does not follow because chairs could be books that are not pens.
Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2022, held on 5 June 2022. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.