  There are two major objections to this theory. First, as Hudson notes, even if we normally count by almost-identity, we know how to count by identity, and when we do it seems that there is one cloud in the sky, not many millions. A defender of Lewis's position may say that the only reason this seems intuitive is that it is normally intuitive to say that there is only one cloud in the sky. And that intuition is respected! More contentiously, it may be argued that it is a good thing to predict that when we count by identity we get the result that there are millions of clouds. After all, the only time we'd do this is when we're doing metaphysics, and we have noted that in the metaphysics classroom, there is some intuitive force to the argument that there are millions of clouds in the sky. It would be a brave philosopher to endorse this as a virtue of the theory, but it may offset some of the costs.