  Endeavoring to formulate an exhaustive solution to the measurement problem in
view of the theory of decoherence leads to a better understanding of the status
of the collapse and of the emergence of classicality, thanks to a precise
definition of the measurement and some new vocabulary to speak about quantum
mechanics. Considering the latter as a probabilistic theory all along allows us
to avoid the usual probability problem of the many-worlds interpretations. A
thorough verification of the consistency of quantum mechanics at all scales is
proposed, as well as a discussion of what can be deemed an observer.
