Choose the correct inference from the statements II. Some researchers are definitely scientists.

Question

Choose the correct inference from the statements

Statements:

I. All scientists are researchers.

II. No researcher is a poet.

Conclusions:

I. No scientist is a poet.

II. Some researchers are definitely scientists.

1. A. Only Conclusion I follows
2. B. Only Conclusion II follows
3. C. Both I and II follow (Correct answer)
4. D. Neither I nor II follow

Correct Answer

Option C — Both I and II follow

Detailed Solution & Explanation

The correct answer is Both I and II follow.

Key Points

• The statements are:
  • I. All scientists are researchers — the set of scientists lies entirely within the set of researchers.
  • II. No researcher is a poet — the sets of researchers and poets are completely separate.
• Testing Conclusion I — "No scientist is a poet": every scientist is inside the researcher circle, and the researcher circle has no overlap at all with the poet circle. A scientist therefore cannot be a poet. This follows.
• Testing Conclusion II — "Some researchers are definitely scientists": since all scientists are researchers, the scientist set is a subset of the researcher set. Reversing a universal affirmative gives a valid particular statement — "some researchers are scientists". This follows.
• Both conclusions are therefore valid.

Additional Information

• The Venn arrangement: draw the scientist circle wholly inside the researcher circle, and place the poet circle completely outside the researcher circle. Conclusion I follows because the scientist and poet circles cannot touch; Conclusion II follows because part of the researcher circle is occupied by scientists.
• Standard conversion rules in syllogism:
  • All A are B → converts to Some B are A (valid), but not to "All B are A".
  • No A is B → converts to No B is A (valid, and fully reversible).
  • Some A are B → converts to Some B are A (valid).
  • Some A are not B → cannot be converted.
• Why "definitely" matters in Conclusion II: in syllogism questions the word signals a definite rather than a possible conclusion. Here it is justified, because a subset relation guarantees the overlap rather than merely permitting it.
• Method: always draw the diagram rather than reasoning verbally, and test whether a conclusion holds in every possible arrangement consistent with the statements — a conclusion that fails in even one arrangement does not follow.