  We consider a constructive modification of quantum-mechanical formalism.
Replacement of a general unitary group by unitary representations of finite
groups makes it possible to reproduce quantum formalism without loss of its
empirical content. Since any linear representation of a finite group can be
implemented as a subrepresentation of a permutation representation,
quantum-mechanical problems can be formulated in terms of permutation groups.
Reproducing quantum behavior in the framework of permutation representations of
finite groups makes it possible to clarify the meaning of a number of physical
concepts.
