 Indeed, what happens if we include decoherence in the description? Decoherence tells us, among other things, that plenty of interactions are taking place all the time in which differently localised states of the apparatus registering, say, different \(x\)-spin values of an electron couple to different states of the environment. But now, by the same arguments as above, the composite of electron, apparatus and environment will be a superposition of (i) a state corresponding to the environment coupling to the apparatus coupling in turn to the value \(+\frac{1}{2}\) for the spin, and of (ii) a state corresponding to the environment coupling to the apparatus coupling in turn to the value \(-\frac{1}{2}\) for the spin. We are thus left with the following choice, whether or not we include decoherence: either the composite system is not described by such a superposition, because the Schrödinger equation actually breaks down and needs to be modified, or it is described by such a superposition, but then we need to either to supplement quantum mechanics with appropriate hidden variables, or to give an appropriate interpretation of the superposition.