The exponentially-damped Breit-Pauli Schrödinger (XBPS) model of nuclear physics is reviewed. A key assumption is that the neutron is a compound of three elementary particles: the proton, the electron and the antineutrino. Binding within the neutron is achieved by assuming that the antineutrino plays an essential role in keeping the particles together. An important aspect of this approach is the choice of its charge-to-mass ratio to lie in the neighborhood of 0.5-0.6 bohr magneton, whereby arguments have been presented to show that such a large value is perfectly consistent with the experimentally known extreme penetrability of neutrinos. Previous calculations with the XBPS model have found that the triplet multiplicity of the deuteron can be explained by assuming, in agreement with the nuclear shell model, that spin-dependent forces are involved in addition to those which are purely electromagnetic in nature. Based on both experimental and theoretical inferences, a “spin-flip” mechanism is proposed to account for the instability of the neutron. The essential role of  e^- ̅ν  complexes of 0- symmetry in producing nuclear binding is emphasized, particularly their attraction for constituent protons in a given nucleus.