posted by jessica on .
is this an example of an invalid argument
All crows are black
John is black
Therefor, John is a crow.
is this an example of a unsound argument
All dogs are black
Lassie is a dog
Lassie is a cat
Please tell me if this is right.
You're right for both arguments.
The premise for the first statement is correct. But obviously the conclusion is wrong -- making the argument invalid.
The premise for the second argument is not correct. Therefore it is both invalid and unsound.