Which of the following is a valid categorical syllogism?
A) "Some animals are mammals. John is an animal. Therefore, John is a mammal."
B) "Some animals are mammals. John is a mammal. Therefore, John is an animal."
C) "No animals are plants. John is a mammal. Therefore, John is not a plant."
D) "No animals are plants. John is an animal. Therefore, John is not a plant."

Question

Quizplus · Accepted Answer

This answer is valid. If, as the major premise asserts, nothing is both an animal and a plant, then anything that is one is not the other. Since John is an animal, he must not be a plant. The argument is deductively valid.

Which of the Following Is a Valid Categorical Syllogism