ABSTRACT
If I told you that I had just met a man with one arm, you would think that I’d met a man with just one arm. But I also have one arm. And another one. Because a man with two arms is also a one-armed man, though a man with just one arm is not a two-armed man. What category of error has been made here? And whose fault is it? Yours or mine? If I told you that I had just met a man with one arm and you think that I’ve met a man with just one arm, the error is this: you’ve mistaken an observation for a claim to exclusivity.
