A field guide to the ways reasoning breaks
Values and premises
Also called Argumentum ad logicam
Concluding a claim is false because the argument given for it was flawed.
Your argument had a fallacy, so your conclusion is false.
Separate the argument from the claim. A bad argument leaves the claim unproven, not refuted.
Catalogued as argumentum ad logicam, 'the argument to logic', and nicknamed the fallacist's fallacy; David Hackett Fischer gave it that name in Historians' Fallacies (1970), and Nigel Warburton lists it as the 'bad reasons fallacy' in Thinking from A to Z. The mistake is to confuse a broken proof with a broken claim.
Her thread argued for the vaccine mandate from a study that turned out to be retracted, so he declared the mandate itself 'debunked' and moved on.
The defense attorney's closing leaned on an emotional appeal, and the jury decided the client must therefore be guilty.
A reviewer spots a straw man in the op-ed and dismisses not just the column but the policy it was arguing for.
Mid-debate, someone calls out a tu quoque and treats the buzzer as a referee's whistle — point scored, position false.