Like the general Appeal to Silence fallacy, the Gish Gallop and Fire Hose of Falsehoods are tactics that involve taking a failure to respond as evidence for a claim.
As a rhetorical tool, the Gish Gallop is an attempt to overwhelm an opponent by presenting many arguments and claims with no concern for their quality or accuracy. The Gish Gallop was named in 1994 by anthropologist Eugenie Scott who claimed that Duane Gish used this tactic when arguing against evolution.
The Gish Gallop is somewhat like the debating tactic of spreading which involves making arguments as rapidly as possible in the hopes that the opponent will not be able to respond to all of them. The main distinction is that the Gish Gallop is an inherently bad faith technique that relies on rapidly presenting weak arguments, fallacies, partial truths, straw men, and lies in the hopes that the opponent will not be able to refute them all. The Gish Gallop can be seen as a metaphorical cluster bomb of fallacies and untruths.
While this technique lacks logical force, it can have considerable psychological force. The Gish Gallop relies on Brandolini’s Law, which is the idea that it takes more time and effort to refute a fallacy or false claim than it takes to make them. Effective use of a Gish Gallop will yield many unrefuted fallacies and false claims, and this can create the impression in the audience that the Gish Galloper has “won” the debate. The Gish Gallop can be combined with Moving the Goal Posts to create the illusion that at least some of the refutations have been addressed.
Psychologically, the side that seems to have made the most unrefuted arguments and claims might appear to be correct, especially if the Gish Galloper uses the Gish Gallop fallacy, which has the following general form:
Premise 1: Person A presented N arguments for claim C.
Premise 2: Person B, the opponent, refuted X of A’s arguments.
Premise 3: N is greater than X.
Conclusion: C is true.
This is fallacious reasoning because it is not the number of arguments that proves a claim, but the quality of the arguments. As an illustration, consider this silly example:
Premise 1: During a debate, Bob presented 123 arguments that 2+2=6.
Premise 2: Bob’s opponent Sally only refuted 2 of Bob’s arguments before time ran out.
Premise 3: 123 is greater than 2.
While the error in reasoning is obvious in such absurd cases, people can easily fall victim to this reasoning in more complicated or controversial cases, especially if the audience does not know the subject well.
One reason why this fallacy might be appealing is that it seems analogous to methods that do work. For example, a swarm of relatively weak ants can overwhelm a strong spider in virtue of their numbers, even though the spider might kill many of them. But argumentation usually does not work like that; weak arguments generally do not add together to overcome a single strong argument. So, the analogy is not a swarm of ants beating a spider, but a spider fighting ants one at a time.
Another reason the fallacy might seem appealing is that making claims or arguments that are not refuted could seem analogous to one team not being able to block every shot taken by their opponent. But the Gish Gallop would be best compared to a basketball team rapidly taking wild shots all over the place, not caring whether they are even in the direction on the basket. The opposing team does not need to block those wild shots; they are not going to score any points. In the case of arguments, not refuting a bad argument does not prove that the argument is good. Not refuting a claim does not prove the claim is true. See Burden of Proof for a discussion of this.
While the Gish Gallop technique involves presenting at least some arguments, a related technique is to blast an opponent with a Fire Hose of Falsehoods. In this context, the Fire Hose of Falsehood is a rhetorical technique in which a large number of falsehoods are quickly presented. The technique can also employ the rhetorical technique of repetition. As a matter of psychological force, the more times a person hears a claim, the more likely they are to believe it. But the number of times a claim is repeated is irrelevant to its truth. This method also often involves using multiple channels to distribute the falsehoods. For example, real users or bots on various social media platforms could be employed to spread the falsehood. This can have considerable psychological force since people are also inclined to believe a claim that (appears to) come from multiple sources. But the number of sources making a claim is irrelevant to the truth of that claim.
This technique can be used to achieve various ends, such as serving as a Red Herring to distract people from an issue or, in its classic role, as a propaganda technique. On a small scale, such as in a debate, it can be used to overwhelm an opponent because a person can usually tell a lie much faster than someone else can refute it. This technique can be used with Moving the Goal Post to exhaust an opponent and run out the clock.
It can also be employed as a variant of the Appeal to Silence. As a fallacy, the reasoning is that unless all the falsehoods made by someone are refuted, then their unrefuted falsehoods are true. As a fallacy, it has this generally form:
Premise 1: Person A makes N falsehoods.
Premise 2: Person B, the opponent, refuted X of A’s falsehoods.
Premise 3: N is greater than X.
Conclusion: The unrefuted falsehoods are true.
Laid bare like this, the bad logic is evident. Not refuting a falsehood does not make the falsehood true. When someone uses this fallacy, they will attempt to conceal the logical structure of this reasoning. They might, for example, simply say that their opponent has not refuted their claims and so their opponent must agree with them.
While this is a fallacy, it can be effective psychologically. If a person seems confident in their falsehoods and overwhelms their opponent with the sheer number of their lies, they might appear to have “won” the debate.
Defense: To avoid being taken in by the Gish Gallop, the key is remembering that the support premises provide to a conclusion is based on the quality of the argument. The quantity of (unrefuted) arguments for a claim, by itself, does not serve as evidence for a claim. In the case of claims, a failure to refute all the claims made a person does not prove that the unrefuted claims are true; this applies to both the Gish Gallop and the Fire Hose of Falsehood.
If a Gish Gallop or Fire Hose of Falsehood is being used against you in a debate, you will almost certainly not be able to respond to all the arguments and claims. From a logical standpoint, one good option is to briefly point out your opponent’s technique and why it is defective. If you are arguing for a position, focus on your positive arguments and, if time permits, respond to the most serious objections. If you are arguing against a position, focus on your arguments against that position and, if possible, try to pre-empt the arguments your opponent is likely to use in their Gish Gallop. You can also sometimes group arguments and claims together and refute them in groups. For example, if an opponent uses multiple Straw Men, you can respond to all of these by pointing this out.
Gus: “So, my opponent is a climate change scientist. That means she hates capitalism, so she is wrong. Also, these so-called climate change scientists say that humans are the only things that affect the climate, that is totally wrong. You remember Al Gore, right? Remember how silly that guy is? Plus, he lost the election! To George Bush! Lots of smart people don’t believe in climate change and how can the climate change if the earth is flat? Remember how they used to call it global warming? Now these scientists say that some places will get cooler! Also, remember that it snowed in Texas. So much for global warming! And we still had winter; it was cold some days. And everyone knows that we had ice ages in the past. But we don’t have an ice age now. So, climate changes without us; so much for the idea that humans are causing it.”
Moderator: “Time. Your turn Dr. Jones. You have two minutes.”
Dr. Jones: “So where to begin…”
Gus, two minutes later: “See, “Dr.” Jones did not refute all my arguments. So, climate change is all a hoax, as I said.”