निम्नलिखित कथनों और निष्कर्षों पर विचार कीजिए :
- कथन 1: कुछ चूहे बिल्लियाँ हैं ।
- कथन 2: कुछ बिल्लियाँ कुत्ते हैं ।
- कथन 3: कोई भी कुत्ता गाय नहीं है ।
- निष्कर्ष I: कोई भी गाय बिल्ली नहीं है ।
- निष्कर्ष II: कोई भी कुत्ता चूहा नहीं है ।
- निष्कर्ष III: कुछ बिल्लियाँ चूहे हैं ।
उपर्युक्त निष्कर्षों में से कौन-सा/से, इन कथनों से निकाला गया/निकाले गए है/हैं ?
Read this question in English
Consider the following Statements and Conclusions:
Statement 1. Some rats are cats.
Statement 2. Some cats are dogs.
Statement 3. No dog is a cow.
Conclusion I. No cow is a cat.
Conclusion II. No dog is a rat.
Conclusion III. Some cats are rats.
Which of the above conclusions is/are drawn from the statements?
(a) I, II and III · (b) Only I and II · (c) Only III · (d) Only II and III
उत्तर और व्याख्या · explanation in English
Answer: (c) केवल III
'Some rats are cats' converts directly into 'Some cats are rats'. The other two conclusions are 'no' statements that would need a definite chain, but the links to cows and to rats run through 'some' statements, which settle nothing.
- Statement 1 converts: some rats are cats → some cats are rats. Conclusion III follows.
- Only the cats that are dogs are kept away from cows (no dog is a cow); the other cats may or may not be cows, so Conclusion I is not certain.
- Rats reach dogs only through cats, by two 'some' links; a rat may or may not be a dog, so Conclusion II is not certain.
- Only III follows.
- ✗ Conclusion I Cats that are not dogs could still be cows; nothing rules it out.
- ✗ Conclusion II Two 'some' statements give no definite link between rats and dogs, either way.
- ✓ Conclusion III It is the direct converse of 'Some rats are cats'.
Remember · A 'some' statement converts both ways; a 'no' conclusion needs an 'all' or 'no' chain — 'some' links never prove it.
Question and answer: UPSC's official GS Paper II (2019, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·