1954–1962. “The Unity of Knowledge”: New Harmonies

Abstract

Bohr’s ultimate interpretation of quantum phenomena and quantum mechanics, discussed in Chap. 9, was, I argue, essentially in place by the late 1930s. His 1949 “Discussion with Einstein on Epistemological Problems in Atomic Physics” reprised this interpretation, via his exchanges with Einstein, although without reflecting on changes in his thinking, in part under the impact of these exchanges. Instead, as also explained in Chap. 9, Bohr’s earlier arguments are presented there through the optics of his later views. Einstein, too, had not proposed significantly new arguments after his 1936 “Physics and Reality,” which refined EPR’s argument, although he continued to offer analogous arguments concerning the EPR-type experiments into the 1940s. As explained in Chap. 8, his 1949 commentary on Bohr in the Schilpp volume essentially refers to Bohr’s 1935 reply to EPR, which, as I noted, Einstein misread (Einstein 1949b, pp. 681–682). Nothing of substance was said there on Bohr’s subsequent thinking, especially Bohr’s ultimate epistemology presented in “Discussion with Einstein,” published in the same volume. Thus, while continuing to shape a broader debate concerning quantum mechanics (this is still the case), substantively the Bohr–Einstein debate was over by around 1950 and in its essential features even earlier, and Bohr’s and Einstein’s views themselves were pretty much settled.