“Theoretical physicists live in a classical world, looking out into a quantum-mechanical world. The latter we describe only subjectively, in terms of procedures and results in our classical domain.”

— John S. Bell, Introduction to the hidden-variable question

"Introduction to the hidden-variable question" (1971), included in Speakable and Unspeakable in Quantum Mechanics (1987), p. 29

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John S. Bell19

Northern Irish physicist 1928–1990

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