Fallacy Fallacy

A: “The majority of people can reduce their bloating by increasing fiber. I’m sure because it worked for me.”
B: “That’s the anecdotal fallacy. Therefore, increasing fiber doesn’t reduce bloating for most people.”

Both speakers commit fallacies here. A uses an anecdote as proof for a general claim (anecdotal fallacy). B assumes the conclusion is false just because A’s reasoning is bad—that’s the fallacy fallacy.

A weak or fallacious argument shows the reasoning fails, but it does not, by itself, show the claim is false.

This isn’t a loophole for sloppy thinking. If an argument contains a fallacy, you should reject that argument. What you cannot do is jump from “this argument is flawed” to “the claim is wrong.”

People may also assume others have committed the fallacy fallacy when they haven’t (even if they don’t mention it by name). For example:

A: “Margarine is unhealthy because it’s unnatural.”
B: “That’s an appeal to nature; how ‘natural’ something is doesn’t tell us about health effects.”
A: “So you think margarine is healthy.”

Here, A both misrepresents B’s point (a straw man) and wrongly assumes B rejected A’s conclusion (i.e., assumes they committed the fallacy fallacy). B never claimed margarine is healthy; B only showed that A’s reason doesn’t support the claim.

Back to the Logical Fallacy Handbook

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