 One way in which the two men’s approaches differed was that Turing’s concerns were rather more general than Church’s, in that (as indicated previously) Church considered only functions of positive integers, whereas Turing described his work as encompassing “computable functions of an integral variable or a real or computable variable, computable predicates, and so forth” (1936: 58). Turing intended to pursue the theory of computable functions of a real variable in a subsequent paper, but in fact did not do so.