 The abstract realm is another interesting target. For this target it is not obvious that there is a sensible type/token  distinction.[4]  So only two of the four natural count policies for concrete objects seem applicable: (i) the number of abstract objects (including derivative ones), and (ii) the number of basic abstract objects (excluding derivative ones). So consider the hierarchy of pure set theoretic objects. One might very naturally be a pluralist about the number of pure set-theoretic abstracta that exist, but a monist about the number of basic set-theoretic abstracta, insofar as one holds that the entire transfinite hierarchy is founded upon a single element: the empty set. Those who reject abstract objects altogether will obviously be nihilists on either count policy (c.f. Goodman and Quine 1947).