Syllogism — Decide which conclusion(s) are necessary Statements: No rabbit is a lion. Some horses are lions. All rabbits are tables. Conclusions: (I) Some tables are lions. (II) Some horses are rabbits. (III) No lion is a table.

Difficulty: Medium

Correct Answer: None follows

Explanation:


Introduction / Context:
We must judge whether any of the conclusions is forced by the premises. Be careful: showing that a conclusion is “possible” is not enough; it must be necessary given the statements.



Given Data / Assumptions:

  • No Rabbit is a Lion (R ∩ L = ∅).
  • Some Horses are Lions (∃ H ∩ L).
  • All Rabbits are Tables (R ⊆ T).


Concept / Approach:

  • From R ⊆ T and R ∩ L = ∅, Rabbits are Tables that are non-Lions; this does not tell us whether other Tables might be Lions.
  • Independence of Horses from Rabbits means we cannot infer overlap unless stated.


Step-by-Step Solution:

(I) “Some tables are lions.” Not necessary. Tables could include many non-rabbit items, but the premises do not force any Table to be a Lion. A compliant model can keep Tables disjoint from Lions except for Horses, which need not be Tables.(II) “Some horses are rabbits.” No link is given between Horses and Rabbits; the overlap is not compelled.(III) “No lion is a table.” Also not compelled. It is consistent that some non-rabbit Tables could be Lions, though not required. Hence this universal negative does not necessarily follow.


Verification / Alternative check:

Construct a model where Tables = Rabbits only. Then Tables and Lions are disjoint, satisfying premises; (I) is false, (III) true in this model, but a different model could add extra Tables overlapping Lions without contradicting premises, making (III) false. Since conclusions vary across valid models, none is necessary.


Why Other Options Are Wrong:

Any option selecting I, II, or III treats a merely possible relation as necessary.


Common Pitfalls:

Assuming “All Rabbits are Tables” implies “All Tables are Rabbits.” It does not; subset is one-way.


Final Answer:

None follows

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