A heuristic approach leads to a suggested fundamental non-linear dynamical equation for a neutral nucleon field operator in Heisenberg representation. Analysis of this equation leads to an equation in momentum space which the fermion propagator must satisfy in a self-consistent manner. This specifies a self-consistent cut-off with at least two additional masses, a ghost one and a real one. To interpret this the Sakata compound model is introduced for the baryon-meson system and extended for reasons of symmetry. A general formally symmetric strong coupling is introduced and discussed. The resultant modification of the fundamental non-linear dynamical equation is then used with the τ-function formalism to generate, in the lowest approximation, the equation of motion of a single baryon, a single meson, and the baryon-baryon interaction. For the lowest approximation for the baryon propagation, a suggested self-consistent baryon propagator is numerically related to the normalization constants, the coupling constant and the mass of the possible meson doublet which the lowest approximation indicates. The significance of this mass doublet is discussed, and the corresponding magnitude of the typical nuclear forces outside the nucleon core is given in the lowest approximation.