 The Grundlagenkrise and his public, polemical exchanges with Brouwer came later, and they gave a distorted picture of the motivations behind his logical investigations. What was the impact of these philosophical debates on the technical aspects of his program? For the formulation of first-order logic, and for the posing of metalogical questions, the answer is easy: there was no impact whatsoever. The contents of Hilbert &amp; Ackermann 1928 were already present in the 1917/18 lectures. As for Hilbert’s proof-theoretic research of the 1920s, the main lines of development emerged quite independently of Brouwer and Weyl. The polemics might have added a sense of urgency, but it is hard to detect any influence on the actual mathematics.