[ Context: I found out about the motte-and-bailey fallacy a few years ago via Scott’s essay All In All, Another Brick In The Motte. I’ve found it a useful concept handle since then, but it’s kind of tricky, many people are not proficient with it, it’s tough to explain in conversation, there’s no existing short post to link to, and the Wikipedia article is long and confusing. So I figured I would write a short explanation myself, so as to be able to link to it. ]
In the Middle Ages, a motte was a fort on a hill. It would be surrounded by a field called a bailey. This was called a motte-and-bailey castle.
[You can remember this by remembering:
the two ’t’s in “motte”, together, look like a little chess rook
“bailey” starts with “ba”, which is the sound a sheep makes, and sheep live in fields]
When the motte-and-bailey castle was attacked, people would retreat to the motte [fort], which was easier to defend. After the attack stopped, they would disperse again to the field and go about their business.
The motte-and-bailey fallacy is when you use a word, or a term, or a phrase, or a concept, like a motte-and-bailey castle, in a way that is hostile to cooperative, or Socratic[/double-cruxing] discussion.
People who are motte-and-baileying are giving a word two different meanings, the same way a motte-and-bailey castle has two different locations with different functions. The “motte” meaning is easy to defend, and it is what they use when they are on the defensive. The “bailey” meaning is the actual conceptual work they use the belief to do in their worldview most of the time.
Example: Aaron tells his wife that each sneeze shortens your life by 10 minutes. This scares her into holding in her annoying sneezes, which is what Aaron intended to accomplish. Aaron’s friend Becky overhears the conversation and later privately calls Aaron out on it, saying there’s no reason to believe that’s true. Aaron tells Becky that he just meant that viral load shortens lifespan, and his wife knew he was just expressing sympathy for her illness. Becky feels abashed and doesn’t press the issue.
Aaron is using “viral load shortens lifespan” as his defensible motte, with Becky.
But “sneezing is literally taking minutes off your life, so you should stop sneezing” is the semantic work he really wants the phrase to do, in the context he really intends on using it in, so it’s his bailey.
Motte-and-Bailey: a Short Explanation
[ Context: I found out about the motte-and-bailey fallacy a few years ago via Scott’s essay All In All, Another Brick In The Motte. I’ve found it a useful concept handle since then, but it’s kind of tricky, many people are not proficient with it, it’s tough to explain in conversation, there’s no existing short post to link to, and the Wikipedia article is long and confusing. So I figured I would write a short explanation myself, so as to be able to link to it. ]
In the Middle Ages, a motte was a fort on a hill. It would be surrounded by a field called a bailey. This was called a motte-and-bailey castle.
[You can remember this by remembering:
the two ’t’s in “motte”, together, look like a little chess rook
“bailey” starts with “ba”, which is the sound a sheep makes, and sheep live in fields]
When the motte-and-bailey castle was attacked, people would retreat to the motte [fort], which was easier to defend. After the attack stopped, they would disperse again to the field and go about their business.
The motte-and-bailey fallacy is when you use a word, or a term, or a phrase, or a concept, like a motte-and-bailey castle, in a way that is hostile to cooperative, or Socratic[/double-cruxing] discussion.
People who are motte-and-baileying are giving a word two different meanings, the same way a motte-and-bailey castle has two different locations with different functions. The “motte” meaning is easy to defend, and it is what they use when they are on the defensive. The “bailey” meaning is the actual conceptual work they use the belief to do in their worldview most of the time.
Example: Aaron tells his wife that each sneeze shortens your life by 10 minutes. This scares her into holding in her annoying sneezes, which is what Aaron intended to accomplish. Aaron’s friend Becky overhears the conversation and later privately calls Aaron out on it, saying there’s no reason to believe that’s true. Aaron tells Becky that he just meant that viral load shortens lifespan, and his wife knew he was just expressing sympathy for her illness. Becky feels abashed and doesn’t press the issue.
Aaron is using “viral load shortens lifespan” as his defensible motte, with Becky.
But “sneezing is literally taking minutes off your life, so you should stop sneezing” is the semantic work he really wants the phrase to do, in the context he really intends on using it in, so it’s his bailey.