  We find an exact general solution to the three-dimensional (3D) Ising model
via an exact self-consistency equation for nearest-neighbors' correlations. It
is derived by means of an exact solution to the recurrence equations for
partial contractions of creation and annihilation operators for constrained
spin bosons in a Holstein-Primakoff representation. In particular, we calculate
analytically the total irreducible self-energy, the order parameter, the
correlation functions, and the joined occupation probabilities of spin bosons.
The developed regular microscopic quantum-field-theory method has a potential
for a full solution of a long-standing and still open problem of 3D critical
phenomena.
