Definition
Motte-and-Bailey Fallacy
The motte-and-bailey fallacy is an informal fallacy that occurs when a speaker alternates between a bailey, a strong and controversial claim, and a motte, a weaker claim that is much easier to defend.
The fallacy occurs when the speaker uses support for the motte as if it also supported the bailey.
Structure
A typical pattern is:
- State the bailey.
- When challenged, retreat to the motte.
- After criticism subsides, return to the bailey.
The move is deceptive because the two claims are not equivalent. Defending the motte does not justify the bailey.
Distinction
The fallacy is not the existence of two claims. It is the silent switch between them. If the speaker explicitly distinguishes the weaker claim from the stronger one, the move is not a motte-and-bailey.
Examples
Example
“This platform should allow any speech.”
When challenged, the speaker retreats to: “People should be free to express opinions.”
The second claim is defensible. The first is much stronger. Using the second to defend the first is the fallacy.