Classical Deductive Logic

A categorical syllogism is a deductive argument with two premises, in which the premises and the conclusion are categorical propositions.

A categorical proposition, in turn, is a statement that makes a straightforward assertion with no "ifs," "ands," or "buts." Categorical propositions are typically expressed by simply structured sentences containing a subject and a predicate, but not conjunctions or the other grammatical devices involved in more complex sentences.


Comprehension Questions

1 Is the following a categorical proposition?
A dog is a mammal, if it has hair.
a) yes
b) no
2 Is the following a categorical proposition?
Either that is a dog, or it is a funny looking cat.
a) yes
b) no
3 Is the following a categorical proposition?
Amphibians breathe from their mouth, except when they are under water.
a) yes
b) no
4 Is the following a categorical proposition?
Those who have the courage to dare will succeed.
a) yes
b) no


Components of Categorical Propositions

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