Well, it's countable in the sense that a countable number of humans have existed, with a countable (or at least bounded) number of idiolects per human. That's p

Well, it's countable in the sense that a countable number of humans have existed, with a countable (or at least bounded) number of idiolects per human. That's pretty much the "point in discrete color space" point of view I was getting at on one extreme. That's not a very useful level of granularity for much else other than upper bounding. At the lower bound, maybe we all just speak and sign dialects of some inherent Chomsky-esque universal grammar. In between, there are all sorts of ways you can draw borders on the map to tesselate it into languages, but few of these schemes can be defined without resorting to idiosyncratic decisions. Language is a social construct. We're colloquial beings, and 99% of the time we all agree on what's what. What irritates me are the folks that think that the remaining 1% can be decided in some kind of objective way. Is Scots its own language? Depends on who you ask, and in what context. There are valid arguments either way. Embrace the ambiguity.