Given below are two statements

Statement I: To obvert a proposition, we change its quality and replace the predicate term with its complement.

Statement II: Obversion is valid for any standard form categorical proposition.

In light of the above statements, choose the correct answer from the options given below 

The correct answer is option 1) Both Statement I and Statement II are true.

Key Points

Statement I: To obvert a proposition, we change its quality and replace the predicate term with its complement.

• Obversion is a logical operation used to form the contrapositive of a proposition.
• It involves changing the quality of the proposition, from affirmative to negative (or vice versa).
• The predicate term is then replaced with its complement, which is the set of all objects that are not included in the original predicate term.
• For example, the obverse of the proposition "All dogs are mammals" is "No dogs are non-mammals." The quality has been changed from affirmative to negative, and the predicate term "mammals" has been replaced with its complement "non-mammals".

Statement II: Obversion is valid for any standard form categorical proposition.

• The standard form categorical proposition can be one of four types: All A are B, No A are B, Some A is B or Some A is not B.
• Obversion can be applied to any of these propositions to create a logically equivalent contrapositive.
• For example, the obverse of the proposition "Some cats are not black" is "Some cats are black." The quality has been changed from negative to affirmative, and the predicate term "black" has been replaced with its complement, which is "non-black."

Therefore, both statements I and II are true, making option 1) the correct answer.