The Fallacy Fallacy Fallacy

Logical fallacies are mistakes in reasoning. Sometimes the problem lies in the structure of the argument itself (formal fallacies), and other times it lies in the content—for example, using ambiguous language or misrepresenting someone’s position (informal fallacies). Either way, the argument fails to justify its conclusion.

You may have heard of the fallacy fallacy, which happens when someone assumes that because an argument contains a logical fallacy, its conclusion must be false. This is a mistake because someone can arrive at a true conclusion for the wrong reasons.

But there is another mistake I’ve been noticing lately: when someone points out that an argument is flawed, others may take this to mean that the critic is also rejecting the conclusion. In other words, they assume the critic is committing the fallacy fallacy. It’s not the most elegant name, but I call this the fallacy fallacy fallacy.

Here’s an example:
A: You should never consume anything with ingredients you can’t pronounce. Therefore, you should never drink antifreeze.
B: The ease with which we can pronounce something’s ingredients tells us nothing about how safe it is to consume.
C: So you think people should drink antifreeze?

Person B was not arguing that people should drink antifreeze. They were pointing out that the reasoning was flawed.

Person C straw-manned Person B by misrepresenting what they were saying. More specifically, Person C treated criticism of the argument as if it were criticism of the conclusion. That is the fallacy fallacy fallacy.

It is important to point out bad reasoning (in a clear, respectful, and helpful way) even when the conclusion is true because that reasoning can be reused in other cases where the conclusion is false and harmful. For example, Person A’s flawed reasoning could be used to argue that we should not consume things that are perfectly safe and even healthy, like foods containing ascorbic acid (vitamin C) or riboflavin (vitamin B2).

But this can be difficult to do when criticism of an argument is assumed to be a rejection of the conclusion. I once saw a social media post arguing for the benefits of vaccines using a logical fallacy. When someone correctly pointed out the fallacy in the comments, they were attacked as being “anti-vax,” even though they explicitly said they supported vaccines.

If we have other good reasons to think a conclusion is true, then criticism of one flawed argument in support of it should not feel threatening. If anything, it’s helpful because it lets us move attention back to the arguments that actually do support the conclusion. A true conclusion is better served by good evidence and sound reasoning than fallacious arguments.