Syllogism — Identify which conclusions are compelled: Statements: • All astronomers are scientists. • Some scientists are shopkeepers. Conclusions: I. All astronomers are shopkeepers. II. Some shopkeepers are astronomers. III. Some shopkeepers are scientists. IV. All scientists are astronomers.
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AOnly Conclusion I follows
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BConclusions I, II and III follows
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COnly Conclusion III follows
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DConclusions II and IV follow
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ENone of these
Answer
Correct Answer: Only Conclusion III follows
Explanation
Introduction / Context:We have one universal inclusion and one existential statement about scientists. We must filter out converses and overstatements, keeping only what the premises force.
Given Data / Assumptions:
- S1: Astronomers ⊆ Scientists.
- S2: Some Scientists are Shopkeepers.
- Conclusions: I “Astronomers ⊆ Shopkeepers”; II “Some Shopkeepers are Astronomers”; III “Some Shopkeepers are Scientists”; IV “Scientists ⊆ Astronomers.”
Concept / Approach:From S2 we immediately know there exist individuals who are both Scientists and Shopkeepers; that alone proves III. However, I and II require information linking Astronomers specifically to Shopkeepers, which we do not have. IV is a converse of S1 and is not supported.
Step-by-Step Solution:1) Take x with Scientist(x) and Shopkeeper(x) from S2 ⇒ CIII holds.2) For I to hold, we would need Astronomers ⊆ Shopkeepers; the premises give no such link.3) For II to hold, some Shopkeeper would have to be an Astronomer; possible but not necessary.4) IV claims Scientists ⊆ Astronomers, the converse of S1; not implied.
Verification / Alternative check:Build a model where Astronomers is a tiny subset of Scientists that does not overlap with Shopkeepers, while some other Scientists are Shopkeepers. Premises true, only III follows.
Why Other Options Are Wrong:Options that include I, II or IV assert more than the premises provide or rely on illicit conversion.
Common Pitfalls:Assuming that because some Scientists are Shopkeepers, subsets of Scientists (Astronomers) are also Shopkeepers; that is invalid without additional information.
Final Answer:Only Conclusion III follows.