Re: [Haskell-cafe] Why is this strict in its arguments?

On Dec 5, 2007 11:56 AM, Andrew Coppin wrote:

I was merely noting that questions of the form "is X decidable?" are usually undecidable. (It's as if God himself wants to tease us...)

I take issue with your definition of "usually" then. Whenever "X is decidable" is undecidable, "'X is decidable' is decidable' is decidable, namely false. So there are at least as many decidable sentences of the form "X is decidable" as there are undecidable ones. Luke