On interactions of static magnetic fields

We investigated the interaction energy of a Gilbertian magnetic charge with each of the "point" magnetic field sources. Finally we extrapolated a Dirac string can only be defined if there is at most one Dirac monopole in the medium. If there is only one Dirac monopole/string in the universe, the probability of detecting it is essential zero, such that Dirac's monopole would remain just a "theorist's particle".