Published online by Cambridge University Press: 01 April 2022
The Bell 1964 theorem states that nonlocality is a necessary feature of hidden variable theories that reproduce the statistical predictions of quantum mechanics. In view of the no-go theorems for non-contextual hidden variable theories already existing up to 1964, and due to Gleason and Bell, one is forced to acknowledge the contextual character of the hidden variable theory which the Bell 1964 theorem refers to. Both the mathematical and the physical justifications of this contextualism are reconsidered. Consequently, the role of contextualism in recent no-hidden-variables proofs and the import of these proofs are investigated. With reference to the physical intuition underlying contextualism, the possibility is considered whether a context-dependence of individual measurement results is compatible with context-independence of the statistics of measurement results.
I wish to thank Roberto Giuntini, Maria Luisa Dalla Chiara, Jeremy Butterfield and Mauro Dorato for very helpful advice and comments at different stages in the preparation of the present paper. I am also grateful to Constantine Pagonis for allowing me to read his Ph.D. dissertation, and to the audience in the Department of History and Philosophy of Science in Cambridge for interesting comments and remarks.