Match List - I with List - II.

List - I (In a square of opposition)		List - II (Result)
A.	If ‘E’ is False	I.	‘O’ is Undetermined
B.	If ‘O’ is True	II.	‘E’ is True
C.	If ‘I’ is False	III.	‘E’ is False
D.	If ‘A’ is True	IV.	‘E’ is Undetermined

Correct option is D

• (A) If ‘E’ is False:

  • If E (universal negative) is false, then O (particular negative) is undetermined. Hence, the result is (I).

• (B) If ‘O’ is True:

  • If O (particular negative) is true, E (universal negative) is undetermined. Hence, the result is (IV).

• (C) If ‘I’ is False:

  • If I (particular affirmative) is false, then E (universal negative) must be true. Hence, the result is (II).

• (D) If ‘A’ is True:

  • If A (universal affirmative) is true, then E (universal negative) is false. Hence, the result is (III).

Thus, the correct matching is,

(A)-(I), (B)-(IV), (C)-(II), (D)-(III).

Information Booster:

1. E (Universal Negative): A proposition of the form "No S are P." It is false if any individual in the subject set is found in the predicate set. It is the opposite of the A proposition, which is a universal affirmative.

2. O (Particular Negative): A proposition of the form "Some S are not P." The truth or falsity of this proposition is determined by the existence or non-existence of individuals in the subject set that do not belong to the predicate set.

3. I (Particular Affirmative): A proposition of the form "Some S are P." If this is false, it indicates that no individuals in the subject set belong to the predicate set, which, in turn, makes the E proposition true.

4. A (Universal Affirmative): A proposition of the form "All S are P." If this proposition is true, it can affect the truth value of other propositions, such as E, which would be false in that case. If A is true, the E proposition is generally false because no subject can belong to the opposite predicate set.

5. Square of Opposition: This logical diagram helps us understand the relationships between different types of categorical propositions (A, E, I, O). The four categorical forms show how truth values are interdependent, meaning that the truth value of one form can influence the others in a structured way.

​