decoherence (that is, with respect to system degrees of freedom that commute most rapidly and efficiently with environmental degrees of freedom). [@Crull p. 1021]

We believe that all these words in quotations only obscure the meaning of these phrases and, more importantly, complicate a conceptual appraisal of their validity. The point, as we said above, is that one must not forget that these expressions are only figures of speech and that, in order to fully evaluate them, they have to be unpacked in formal terms. The problem, as we will see below in detail, is that, in doing so, one finds that decoherence in fact does not accomplish what it is supposed to.

In order to start such unpacking, we note that decoherence is supposed to solve the measurement problem and to explain the emergence of classicality by accomplishing two things (see [@Sch p. 6]):

1.  Suppression of macroscopic interference.

2.  Selection of a preferred basis.

In words of Zurek:

> Decoherence destroys superpositions. The environment induces, in effect, a superselection rule that prevents certain superpositions from being observed. Only states that survive this process can become classical. [@Zur p. 21]

Therefore, in order to evaluate the ability of decoherence 