Argument from fallacy

An argument from fallacy, or the fallacy fallacy is a formal fallacy which occurs when analyzing an argument and assuming that, because the argument contains a logical fallacy the conclusion of that argument must be false. It is also commonly referred to as the fallacist's fallacy.

Form

The form of the argument from fallacy requires a meta-argument, or an argument about the claims of an argument.

The issue here is that while the presence of a fallacy is sufficient to render argument A invalid, it does not make C false. Rather, the truth value of C is unknown, because there is no valid argument as to whether C is true or false.