  The possibility of consistency between the basic quantum principles and
reduction (wave function reduction) is reexamined. The mathematical description
of an organized macroscopic device is constructed explicitly as a convenient
tool for this investigation. A derivation of reduction from quantum mechanics
is proposed on a specific example, using standard methods of statistical
physics. Although these methods are valid only "for all practical purposes",
arguments are given to ascribe an emerging status to reduction (or the
uniqueness of physical reality), similar to the status of classical physics.
Examination of measurements of the particles in an EPR pair by two space-like
separated apparatuses shows that the model is consistent with the non-separable
character of quantum mechanics, although both measurements are local.
Quantitative estimates are given.
