The abrupt transition from quantum to classical that is implied by wave function collapse is ‘a “magic” process’, he wrote to Jammer in 1973, quite unlike other physical processes, which ‘obey perfectly natural continuous laws’. The ‘artificial dichotomy’ created by the ‘cut’, he said, is ‘a philosophic monstrosity’.

Ananyo Bhattacharya, The man from the future: the visionary life of John von Neumann, London, 2021