  Superconductivity is macroscopic quantum phenomenon. From force of habit most
physicists pay no heed to a paradoxicality of this fact. Niels Bohr considered
quantum mechanics as atomic physics and the paradoxical quantum principles may
be admissible on this level. But they seem quite strange on the macroscopic
level. In the last years some experts, A. J. Leggett and other, attract our
attention to a contradiction between quantum mechanics and macroscopic realism.
In this paper I try to draw reader's attention to some paradoxical consequences
of the Bohr quantization on the macroscopic level.
