Stewart SHAPIRO Philosophy of Mathematics Oxford: Oxford University Press 2000 end p.iii Numbers . . . are known only by their laws, the laws of arithmetic, so that any constructs obeying those laws—certain sets, for instance—are eligible . . . explications of number. Sets in turn are known only by their laws, the laws of set theory . . . arithmetic is all there is to number . . . there is no saying absolutely what the numbers are; there is only arithmetic. Quine [1969, 44-45] 1 Slogans 2 Methodology