Since both the premises are particular, no definite conclusion follows. However, I and III involve only the extreme terms and form a complementary pair. Thus, either I or III follows.
2. Statements: All politicians are honest. All honest are fair.
Clearly, it follows that 'All politicians are fair'. I is the converse of the first premise, while III is the converse of the above conclusion. So, both I and III hold.
3. Statements: All aeroplanes are trains. Some trains are chairs.
Since the middle term 'trains' is not distributed even once in the/premises, no definite conclusion follows. However, III is the converse of the second premise while IV is the converse of the first premise. So, both of them hold.
4. Statements: Some bags are pockets. No pocket is a pouch.
Since one premise is particular and the other negative, the conclusion must be particular negative and should not contain the middle term. So, II follows. III is the converse of the first premise and thus it also holds.
5. Statements: All branches are flowers. All flowers are leaves.
Since both the premises are universal and affirmative, the conclusion must be universal affirmative and should not contain the middle term. So, it follows that 'All branches are leaves'. Thus, I follows. IV is the converse of this conclusion and so it also holds.
6. Statements: All terrorists are guilty. All terrorists are criminals.
Conclusions:
Either all criminals are guilty or all guilty are criminals.
Since the middle term 'terrorists' is distributed twice in the premises, the conclusion cannot be universal. So, it follows that 'Some guilty persons are criminals'. Thus, II holds.
7. Statements: Some books are pens. No pen is pencil.
Since one premise is particular and the other negative, the conclusion must be particular negative and should not contain the middle term. Thus, III follows. I is the converse of the first premise and so it also holds.
8. Statements: Some bottles are drinks. All drinks are cups.
Since one premise is particular, the conclusion must be particular and should not contain the middle term. So, it follows that 'Some bottles are cups'. Thus, I follows. II is the converse of the second premise and so it also holds.
9. Statements: Some houses are offices. Some offices are schools.
Correct Answer: Only II and IV and either I or III follow.
Explanation:
Since both the premises are particular, no definite conclusion follows. However, I and III involve only the extreme terms and form a complementary pair. So, either I or III follows. II is the converse of the first premise while IV is the converse of the second premise. Thus, both of them hold.
10. Statements: Some taxis have horns. Some taxis have lights.