## Categorical Syllogisms

If an argument has two categorical premises and a categorical conclusion, and the two categorical premises jointly support the conclusion, then this argument is a categorical syllogism.

Example:

 All mammals are animals that breathe by means of lungs. All whales are mammals. Therefore, all whales are animals that breathe by means of lungs.

Comprehension Questions
 1. What kind of propositions are the premises of a categorical syllogism? a) hypothetical and categorical b) disjunctive and categorical c) categorical only d) all of the above 2. A categorical proposition is a) a proposition that makes an assertion about the relations of classes b) a proposition that asserts that the truth of one proposition is sufficient for the truth of another c) a proposition which asserts that either one or another of two propositions is true 3. How do the premises support the conclusion in a categorical syllogism? a) jointly b) independently c) either jointly or independently 4. Is the following argument a categorical syllogism?If you play with fire, you will get burned.You played with fire.You got burned. a) Yes b) No 5. Is the following a categorical syllogism?No horned animal is a carnivore.All moose are horned animals.No moose is a carnivore. a) Yes b) No 6. Is the following argument a categorical syllogism?Either my book is in my bag or I left it in the library. My book is not in my bag.I left my book in the library. a) Yes b) No 7. Is the following argument a categorical syllogism?All supporters of the nuclear freeze want to preserve peace. No conservatives support the nuclear freeze. No conservatives want to preserve peace. a) Yes b) No

Structure of a Categorical Syllogism

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