 The phrase “criterion of identity” seems to mean a criterion which gives a necessary and sufficient condition for identity. In many cases, however, a weaker condition suffices for counting. To conclude that there are exactly two Gs in region S, all that is required is a sufficient condition for x and y to be distinct, and a sufficient condition for z to be identical with x or y. In the case of physical objects, it may be that being at the same location at the same time is sufficient for identity, and being in entirely separate locations at the same time is sufficient for distinctness. In most circumstances, these will suffice to count Gs, but it is far short of providing answers about partially overlapping Gs, and provides no guidance about identity across time. So often we may be able to count Gs without having a criterion of identity in the strong sense.