We discuss proofs of nonlocality based on a generalization by Erwin Schrodinger of the argument of Einstein, Podolsky and Rosen. These proofs do not appeal in any way to Bells inequalities. Indeed, one striking feature of the proofs is that they can be used to establish nonlocality solely on the basis of suitably robust perfect correlations. First we explain that Schrodingers argument shows that locality and the perfect correlations between measurements of observables on spatially separated systems implies the existence of a non-contextual value-map for quantum observables; non-contextual means that the observable has a particular value before its measurement, for any given quantum system, and that any experiment measuring this observable will reveal that value. Then, we establish the impossibility of a non-contextual value-map for quantum observables {it without invoking any further quantum predictions}. Combining this with Schrodingers argument implies nonlocality. Finally, we illustrate how Bohmian mechanics is compatible with the impossibility of a non-contextual value-map.
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