Abstract: Wittgenstein's treatment of number words and arithmetic in the Tractatus reflects central features of his early conception of philosophy. In rejecting Frege's and Russell's analyses of number, Wittgenstein rejects their respective conceptions of function, object, logical form, generality, sentence, and thought. He, thereby, surrenders their shared ideal of the clarity a Begriffsschrift could bring to philosophy. The development of early analytic philosophy thus evinces far less continuity than some readers of Wittgenstein, from Russell and the Vienna positivists to many contemporary readers of the Tractatus, have supposed.

Keywords: analytic philosophy, ascription, Begriffsschrift, Frege, function, logical form, number, Russell, Tractatus, Wittgenstein,