Lincoln: How many legs does a horse have?

Witness: Four.

Lincoln: If we call a tail a leg, then how many legs does a horse have?

Witness: Well, I suppose the horse would have five legs.

Lincoln: Absolutely not, that’s wrong. Calling a tail a leg doesn’t make it a leg!


  • When you specify counterfactuals, you still have to do this in your actual language.1
  • This correctly asserts that changing one’s way of talking does not affect the order of being (this is one way of characterizing the order of being), though it can affect the order of explanation.


  1. Two-dimensional modal logic is supposed to be a technical tool to allow us to specify counterfactuals in other languages.