  As noted above, the two forms of nominalism are independent. The possibility of being a nominalist in one sense but not in the other has been exemplified in the history of philosophy. For instance, David Armstrong (1978; 1997) is a believer in universals, and so he is not a nominalist in the sense of rejecting universals, but he believes that everything that exists is spatiotemporal, and so he is a nominalist in the sense of rejecting abstract objects. And there are those who, like Quine at a certain point of his philosophical development (1964; 1981), accept sets or classes and so are not nominalists in the sense of rejecting abstract objects and yet reject universals and so are nominalists in the sense of rejecting universals.