  A previously published model of the isothermal Maxwell demon as one of models
of open quantum systems endowed with faculty of selforganization is
reconstructed here. It describes an open quantum system interacting with a
single thermodynamic bath but otherwise not aided from outside. Its activity is
given by the standard linear Liouville equation for the system and bath. Owing
to its selforganization property, the model then yields cyclic conversion of
heat from the bath into mechanical work without compensation. Hence, it
provides an explicit thought construction of perpetuum mobile of the second
kind, contradicting thus the Thomson formulation of the second law of
thermodynamics. No approximation is involved as a special scaling procedure is
used which makes the kinetic equations employed exact.
