Sometimes because a person already believes so strongly in the truth of the conclusion and premises, they think the argument that puts them together must be valid. This happens often with proofs for and against God’s existence: the believers or nonbelievers are so convinced of their conclusions that they fail to recognize that they do not actually follow from the premises given. . The problem with the earlier argument about six-legged bugs and spiders is that it is valid but it is not sound.
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