Argument from fallacy is the formal fallacy of analyzing an argument and inferring that, since it contains a fallacy, its conclusion must be false. It is also called argument to logic , the fallacy fallacy, the fallacist's fallacy, and the bad reasons fallacy. While fallacious arguments cannot arrive at true conclusions, they can contain them, so this is an informal fallacy of relevance.
Form
It has the general argument form: Thus, it is a special case of denying the antecedent where the antecedent, rather than being a proposition that is false, is an entire argument that is fallacious. A fallacious argument, just as with a false antecedent, can still have a consequent that happens to be true. The fallacy is in concluding the consequent of a fallacious argument has to be false. That the argument is fallacious only means that the argument cannot succeed in proving its consequent. But showing how one argument in a complex thesis is fallaciously reasoned does not necessarily invalidate its conclusion if that conclusion is not dependent on the fallacy.
Examples
Objection
Both of Bill's rebuttals are arguments from fallacy. Ginger may or may not be a cat, and Tom may or may not be English. The fact that Tom's argument was fallacious is not, in itself, a proof that his conclusion is false.
Counterargument
That one can invoke the argument from fallacy against a position does not prove one's own position either, as this would be an argument from fallacy itself, as is the case in Joe's argument.
Argumentum ad logicam can be used as an ad hominem appeal: by impugning the opponent's credibility or good faith, it can be used to sway the audience by undermining the speaker rather than by addressing the speaker's argument. William Lycan identifies the fallacy fallacy as the fallacy "of imputing fallaciousness to a view with which one disagrees but without doing anything to show that the view rests on any error of reasoning". Unlike ordinary fallacy fallacies, which reason from an argument's fallaciousness to its conclusion's falsehood, the kind of argument Lycan has in mind treats another argument's fallaciousness as obvious without first demonstrating that any fallacy at all is present. Thus in some contexts it may be a form of begging the question, and it is also a special case of ad lapidem.
