I've been making myself more of a nuisance than usual. I've been asking people whether ice and steam are water. Does it matter? Well, if ice or steam isn't water, then water is not just H2O. And that is good to know. But the question sort of grew on me, as questions often do.
The result of my informal survey is that there is simply no consensus on the question. A number of people told me that ice that is frozen water, and hence it's water. On the other hand, my five-year-old son thought that ice is frozen water, and hence it's not water. At issue here, I suppose, is whether "frozen" is an alienans adjective like "fake" in "fake silk" (fake silk isn't silk). After all, as a colleague pointed out, a vaporized human isn't a human. The best argument I heard for the "ice isn't water" position was that if someone gives you a glass of just ice, and you say "I'd like some water in it", nobody will say "There already is water in it." But, still, there is no consensus.
So this is interesting. The case of water and ice is not a far-fetched case, like many cases in metaphysics. It's an entirely familiar, day-to-day case. And yet, as far as I can tell, our use underdetermines our meaning. Scary. If that's what happens with water, what about substance and simultaneity?
My linguistic intuitions are so polluted that they're barely worth asking about. But my inclination is to say that "water" is ambiguous in the way "man" is: there is water in the generic sense and water in the specific sense, and the water in the specific sense is the liquid phase of water in the generic sense. But the informal discussions make me unsure about this.