Hastings & Rother

Logical Exercises (1)

Brief guide to your logical competence
Please answer the following question in all seven arguments below:

Question 1: Is this a VALID argument? If yes, why?
Please remember that, the truth value of the premises and the conclusion is not relevant in deciding the validity of an argument. A VALID argument is one in which the conclusion follows the premises.

Argument type 7:
Cats are birds.
Tigers are birds.
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Therefore, tigers are cats.

Argument type 3:
Cats are mammals.
Tigers are mammals.
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Therefore, tigers are cats.

Argument type 4:
Dogs are cats.
Cats are birds.
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Therefore, dogs are birds.

Argument type 5:
Cats are birds.
Dogs are birds.
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Therefore, dogs are cats.

Argument type 6:
Cats are birds.
Birds are mammals.
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Therefore, cats are mammals.

Argument type 2:
Cats are mammals.
Tigers are cats.
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Therefore, tigers are mammals.

Argument type 1:
Cats are mammals.
Dogs are mammals.
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Therefore, dogs are cats.