 As mentioned above, the article (Bell 1964) in which Bell’s theorem first appeared is a follow-up to Bell (1966), which explores the prospects for hidden-variables theories in which the outcome of an experiment performed is predetermined by the complete state of the system. The introduction to Bell (1964) begins with mention of theories with additional variables that are to restore causality and locality, and says that “In this note that idea will be formulated mathematically and shown to be incompatible with the statistical predictions of quantum mechanics.” The locality assumption is glossed as the requirement “that the result of a measurement on one system be unaffected by operations on a distant system with which it has interacted in the past.” Applied to the case at hand, of Stern-Gerlach experiments performed on an entangled pair of spin-1/2 particles, this is “the hypothesis ... that if the two measurements are made at places remote from one another the orientation of one magnet does not influence the result obtained with the other.” Bell follows this with,