Evaluating Arguments

To prove a conclusion, an argument must have two essential attributes.

First, its premises must be true. An argument is a method of establishing the truth of a proposition by relating it to facts we already know. So we have to start from facts; false premises don't prove anything.

Second, the premises must be logically related to the conclusion in such a way that if the premises are true, the conclusion is likely to be true as well.

We refer to this second attribute--the capacity of the premises to support the conclusion--as the logical strength of the argument.

Logical Strength

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