Argument from fallacy, or the fallacy fallacy, is a logical fallacy that is based on the assumption that an argument containing logical fallacies cannot have a true conclusion. It occurs frequently in various types of discussions and debates, both online and in real-life.
This erroneous line of reasoning is important to understand, in particular for someone who participates in debates or has an interest in logic and argumentation since they are more prone to falling prey to it themselves.
Definition
The argument from fallacy occurs when a person claims that the conclusion of an argument must be wrong because the argument made for it contains a logical fallacy.
As such, this fallacy takes the following logical form:
- Premise 1: Argument A supports conclusion X.
- Premise 2: Argument A contains a logical fallacy.
- Conclusion: Therefore, conclusion X is false.
It is based on faulty reasoning because, even if an argument contains a logical fallacy, it doesn’t mean that its conclusion is necessarily wrong. It is entirely possible – although not desirable by any means – to use a fallacious argument in an attempt to support any true proposition, without affecting its truth value.
Note that this doesn’t imply that it is wrong to point out when someone makes a fallacious argument: in most situations, it is reasonable to do so. Rather, we shouldn’t declare something to be false just because a certain argument made for it is incorrect.
Examples
Example 1
An example of the fallacy fallacy would be:
- Andy: “If I have the flu, then I have a sore throat. I have a sore throat, so, therefore, I have the flu.”
- Sarah: “You have committed the fallacy of affirming the consequent. Therefore, you are wrong and you don’t have the flu.”
It is true that Andy’s argument is logically flawed; it’s possible to have a sore throat without having the flu. However, the fact that the argument contains a logical fallacy doesn’t mean that its conclusion cannot be true: as far as we know, Andy may really have the flu.
Example 2
- Chris: “Many people are on a low-carb diet to lose weight. It must be the best way to do it, all those people can’t be wrong.”
- Derek: “That is actually a fallacious claim. Therefore, it’s safe to say that a low-carb diet is not the best way to lose weight.”
In this example, Chris’s claim contains a logical fallacy known as the appeal to popularity. The fact that a lot of people are doing a certain thing is not proof that it is the best or right thing to do.
However, Derek in turn commits the argument from fallacy by asserting that Chris’s claim must be false simply based on the notion that his reasoning is fallacious. We would need to employ completely different methods to find out if the low-carb diet is really the best way to lose weight or not.
Example 3
- Delilah: “I believe that there must be another planet with intelligent life on it.”
- Hank: “What could you know about this, you didn’t even go to college!”
- Delilah: “Well, the fact that you have to use an ad hominem attack only proves my claim right.”
As in the example above, even though Hank does fall prey to a fallacy, it doesn’t proof that Delilah’s claim is true, or false for that matter.
Related Fallacies
Inverse Fallacy Fallacy
As the name suggests, the inverse fallacy fallacy works the opposite way than the topic of this article. It occurs when one claims that an argument must be sound and valid because its conclusion is true.
As such, its logical form goes as follows:
- Premise 1: Argument A supports conclusion X.
- Premise 2: Conclusion X is true.
- Conclusion: Therefore, argument A does not contain logical fallacies.
For example:
- Andy: “If I have the flu, then I have a sore throat. I have a sore throat, therefore, I must have the flu.”
- Sarah: “Well that doesn’t make much sense.”
- Andy: “But I really do have the flu, so my argument must be correct too!”
Just because Andy’s conclusion happens to be true, doesn’t mean that the argument is necessarily valid. It’s clear why this logic cannot work as it could be applied to any claim that holds a correct statement.
Bad Reasons Fallacy
The bad reasons fallacy works by claiming that a conclusion must be incorrect if the reasons given for it are bad or false.
In other words, if an argument provides us with “bad reasons” – whether because it’s logically invalid or the evidence is insufficient – to believe the truthfulness of its conclusion, it must not be true. This is similar to the fallacy fallacy, but the only difference is that, in the former, the argument doesn’t have to contain a logical fallacy.
As such, the bad reasons fallacy is based on the assumption that a true proposition cannot be supported with erroneous reasoning. However, as explained previously, it is possible to use a bad or fallacious argument to support a conclusion that is correct.
Links:
