Difficulty: Medium
Correct Answer: Only conclusion II follows.
Explanation:
Introduction / Context:
This question examines your understanding of how particular and universal statements combine in syllogism. The sets involved are flies, ants, and insects. You must decide whether the conclusions about these sets are forced by the given statements. The key ideas are subset relations and the difference between some and all type claims.
Given Data / Assumptions:
- Statement 1: Some flies are ants. At least one fly is also an ant.
- Statement 2: All insects are ants. Every insect lies inside the set of ants.
- There is no direct statement about the relation between flies and insects.
- Conclusions I and II must be tested using these two statements only.
Concept / Approach:
The statement Some flies are ants tells us about a non empty overlap between flies and ants. The statement All insects are ants tells us that insects form a subset of ants. A conclusion is valid only when it must hold for every possible situation that respects these two statements. If there is a valid arrangement where a conclusion is false, then the conclusion does not follow. We must beware of overgeneralising from some to all and of assuming extra links that the statements do not provide.
Step-by-Step Solution:
Step 1: Visualise three sets: flies, ants, and insects. From Statement 1, draw an overlapping region between flies and ants to represent some flies being ants.
Step 2: From Statement 2, place the insect set entirely inside the ant set, because all insects are ants.
Step 3: Check Conclusion I, which says all flies are ants. The first statement only tells us that some flies are ants. There may be flies that are not ants, because nothing in the statements forces every fly into the ant set. Therefore, we cannot say that all flies are ants. Conclusion I does not follow.
Step 4: Check Conclusion II, which states that some ants are insects. Since all insects are ants, every insect is an ant. In most exam style reasoning, a universal statement of the form all insects are ants is understood to describe a real non empty class, so there exist some insects. Those insects are ants, which means some ants are insects.
Step 5: Thus, Conclusion II must hold in any realistic model where insects actually exist. The question is framed in a real world context, so we treat the class of insects as non empty and accept that some ants are insects.
Verification / Alternative check:
To verify with an example, suppose there are 100 ants, of which 10 are insects and 20 are flies. Let 5 of the flies also be ants. This fits both statements: some flies are ants and all insects are ants. In this scenario, it is clearly false that all flies are ants, because there are flies outside the ant set. However, some ants are insects, since those 10 insects are all ants. This confirms that Conclusion II follows and Conclusion I does not.
Why Other Options Are Wrong:
- Options that include Conclusion I assume a universal statement about flies which is not given.
- The option claiming that both conclusions follow is wrong because we have just seen a counterexample to Conclusion I.
- The option that rejects both conclusions ignores the clear subset relation between insects and ants.
- The cannot be determined option is incorrect because under normal exam conventions we treat the class insects as non empty, making Conclusion II logically valid.
Common Pitfalls:
Many candidates mistakenly convert Some A are B into All A are B, or they hesitate to accept conclusions involving some when a universal premise is present. It is also common to ignore the practical meaning of everyday sets like insects and treat them as possibly empty. In competitive exams, when such real world sets are used, they are normally understood to exist, which justifies conclusions like some ants are insects.
Final Answer:
Therefore, only the second conclusion is logically supported, and the correct answer is Only conclusion II follows.
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