I frequently find myself reading discussions where people use Informal Fallacies as if they are invincible battering rams that destroy any argument they encounter.

For example, somebody might say "that source is biased because x, y and z good reasons," and the person who brought up the source will say "that is an ad homonym".

Or they might say "data published by x institution is not reliable because the institution is extremely partisan," and somebody will say "that is well poisoning".

I might say that horses are odd-toed except for that genetically modified horse over there, and someone will shout 'No true scotsman! Claim invalid!'

So what I want to know is, is there a name for either of the following:

  1. A tendency to over-identify informal fallacies in a discussion, and/or
  2. The assumption that because an argument contains an informal fallacy it must be false.
  • 1
    2) is the argument from ignorance, [q.v.logicallyfallacious.com/tools/lp/Bo/LogicalFallacies/56/… and 1) is a normal lead-up to it. By destroying the argument in numerous ways, you still don't prove anything, but by investing the effort, you can appear to do so.
    – user9166
    Feb 21, 2017 at 17:32
  • What about when somebody uses the presence of logical fallacies to try to invalidate a reasonable decision-making heuristic/probability judgement? I'm thinking of something like the fact that if I lie five times, you will justifiably say I'm probably lying the sixth time, which is reasonable, probably true, and a logical fallacy. Feb 21, 2017 at 21:35
  • An unreliable source can communicate correct information improperly. Heuristics do not apply to logic, only to politics. You can play the odds it is not worth listening to someone, but that is a political decision. It might we warranted, but it is not logically correct. You cannot consider it evidence in any relevant philosophical sense. (Even politically, they might lie to set you up to distrust them and then look stupid.)
    – user9166
    Feb 21, 2017 at 21:40
  • 1
    The fallacies are either identified correctly or they are not (disregarding ambiguous case). If they are not then the mistake is misidentification of the fallacy and there is no point inventing a special name for that. If they are it doesn't matter how often it happens. Not every undesirable debating tactic is a fallacy.
    – Conifold
    Feb 21, 2017 at 22:56
  • I don't think there is such a fallacy, but perhaps there should be...! Feb 22, 2017 at 14:19

2 Answers 2


I really like your question and I share your frustration at the way people overuse and misuse references to fallacies. For some very unfortunate reason there are many people around who think that logic is the study of fallacies and who think the way to assess an argument is to hunt for fallacies in it. We get endless questions on this site of the form, "what is the name of this fallacy..." and the answer I want to scream at the questioner each time is: it doesn't matter - forget about names of fallacies and just learn to think critically.

I suspect the reason this happens is that people think of logic only in the context of an argument with other people, and they treat an argument as a kind of game in which if you can name a relevant fallacy you win. The most important reason to study logic is to improve your own reasoning and avoid errors. To this end there is some value in learning about common fallacies, so you don't commit them yourself, but it is important not to get hung up on it.

Claims of informal fallacies are in effect a kind of reasoning by analogy. They amount to a claim that an argument is defective because it resembles in relevant respects some paradigm case of a defective argument. Reasoning by analogy can be helpful and persuasive, but there is always the hazard of stretching the analogy too far. Real-life arguments are often subtle and nuanced and depend on considerations for which no obvious relevant paradigm is available.

As a matter of practical advice, I suggest that if someone objects to an argument on the basis of an informal fallacy, challenge them to say what is wrong with this particular argument without appeal to the general category of the fallacy. What is it about this argument that makes them think it resembles the paradigm? Answering that question will give you an opportunity to respond.

When you ask, "...is there a name for... a tendency to over-identify informal fallacies..." you seem to be falling into the very error that you criticise in others. Although if we understand the request in a strictly ironic sense, then I propose we define a new fallacy as follows: The Lazyman Fallacy := the fallacy of supposing you can defeat an argument just by appealing to a named fallacy.

  • i agree with this!
    – user6917
    Feb 22, 2017 at 2:39
  • As for the last paragraph, the question is meant seriously, but the use I intend to make of the answer is to childishly try to one-up players of the spot-the-fallacy game. Luckily there are no rules on stack exchange (as far as I know?) about not using quality answers for any base purpose Feb 22, 2017 at 3:47
  • @BugCatcherNakata there's also the fallacy fallacy which seems to capture the "childish game" component. Frankly, I'm of the opinion that naming and studying informal fallacies tends to do more harm than good for many of the same reasons already noted. Whenever I teach logic I never include a unit on informal fallacies (or fallacies more generally) except to caution against using them as a proxy for actually thinking about the claims made.
    – Dennis
    Feb 22, 2017 at 19:54

One of the questions the OP asks is whether there is a name for the following:

The assumption that because an argument contains an informal fallacy it must be false.

As Dennis mentions in a comment there is the "fallacy fallacy" or "argument from fallacy" that describes this deceptive argument. Here is how Bo Bennet describes it:

Concluding that the truth value of an argument is false based on the fact that the argument contains a fallacy.

However, even citing this fallacy against one's opponent does not mean that the opponent's position is wrong either. Nor does it mean that the opponent has no good reason to point out an informal fallacy.

So regarding the original argument, the reason the opponents are arguing in the first place, one opponent accusing the other of a fallacy is a distraction. Because of that the tactic may be an instance of a "red herring". That is another fallacy that Bennett describes:

Attempting to redirect the argument to another issue to which the person doing the redirecting can better respond. While it is similar to the avoiding the issue fallacy, the red herring is a deliberate diversion of attention with the intention of trying to abandon the original argument.

This assumes the person making the accusation (or counter-accusation) is better able to justify that accusation rather than pursue the original argument.

Bennett, B. Argument from Fallacy. Retrieved on June 13, 2019 from Logically Fallacious at https://www.logicallyfallacious.com/tools/lp/Bo/LogicalFallacies/51/Argument-from-Fallacy

Bennett, B. Red Herring. Retrieved on June 13, 2019 from Logically Fallacious at https://www.logicallyfallacious.com/tools/lp/Bo/LogicalFallacies/150/Red-Herring

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