 In Scientific Thought (1923) Broad rejects the Eternalism he had defended in his (1921a) article. He now advances a theory that “accepts the reality of the present and the past, but holds that the future is simply nothing at all” (1923, p. 66). An all-important corollary of this Growing Block Theory is the thesis that temporal passage is a fundamental feature of reality. This feature is accounted for in terms of what Broad holds is the most fundamental form of change, becoming. Becoming is the coming into existence of events.