  As uttered in this context the sentence is entirely innocuous, and hence clearly expresses a proposition (call this proposition ‘\(p\)’). The problem, however, arises when we evaluate \(p\) relative to a possible world \(w\) in which the thing I am thinking about is the number two. (Crucially, note that we are evaluating the very same proposition \(p\), not the proposition that would have been expressed by (15) had it been uttered in \(w\)). Relative to \(w\), \(p\) is a proposition which effectively ascribes to the number two the property of being green. The example does not quite provide us with an example of a contentful category mistake (arguably, since (15) is actually uttered in the innocuous context, it is not itself a category mistake), but it does suggest that some propositions succeed in ascribing colour properties to numbers, and hence this kind of predication shouldn’t in general be an obstacle to generating contents.