The question contains some statements followed by some conclusions. Decide…
20252023
The question contains some statements followed by some conclusions. Decide which of the given conclusions logically follow from the given statements, disregarding commonly known facts.
Statements:
All parks are roads.
Some roads are malls.
Conclusions:
I. All malls are roads.
II. All malls are parks.
III. Some parks are malls.
IV. No park is a mall.
- A.
Only I follows.
- B.
Only II follows.
- C.
Either I or II follows.
- D.
None follows
Show answer & explanation
Correct answer: D
In syllogism, when a universal premise (All A are B) is combined with a particular premise (Some B are C) that shares the middle term B, no conclusion connecting A and C follows with certainty. The middle term is undistributed in the particular premise, so the specific part of B referred to by ‘some’ need not include any A at all — a conclusion counts as following only if it holds in every diagram consistent with the premises, not just in one possible arrangement.
Applying this to the statements:
From ‘All parks are roads’, the entire park set lies inside the road set.
From ‘Some roads are malls’, only a part of the road set overlaps with the mall set; the premises do not fix whether this overlapping part lies inside or outside the park set.
Conclusion I (All malls are roads) wrongly converts the particular premise ‘Some roads are malls’ into a universal statement about malls — this conversion is not logically valid.
Conclusion II (All malls are parks) has no premise linking malls to parks at all, so it cannot be derived.
Conclusion III (Some parks are malls) would require the road–mall overlap to fall inside the park region — one valid diagram allows this, but another equally valid diagram places the entire overlap outside the park region, so it is not certain.
Conclusion IV (No park is a mall) would require the road–mall overlap to fall entirely outside the park region — again true in only one of several valid diagrams, not a certainty.
Cross-check: drawing two valid Venn diagrams — one with the road–mall overlap placed fully inside the park circle, and one with it placed fully outside — shows conclusions III and IV each hold in one diagram but fail in the other. Since a conclusion must hold in every valid diagram to count as following, none of the four qualifies.
Hence, none of the given conclusions follows from the statements.