Virtually all natural concepts are vague and various scholars have argued that vagueness plays an important role in grammar . 20 Our claim is that if we integrate singular / plural structures with vagueness , we ca n't really miss where the mass / count distinction comes from and the mass / count contrast gets to be explained in terms of independently needed notions . This will constitute the main argument , I submit , for the present proposal . In what follows , I first present the idea in informal terms , then I spell it out with supervaluations / data semantics .