Subtractability and Concreteness

I consider David Efird and Tom Stoneham's recent version of the subtraction argument for metaphysical nihilism, the view that there could have been no concrete objects at all. I argue that the two premises of their argument are only jointly acceptable if the quantifiers in one range over a different set of objects from those which the quantifiers in the other range over, in which case the argument is invalid. So either the argument is invalid or we should not accept both its premises.