Pion-Nucleon Scattering When the Coupling Is Weak and Extended

The symmetrical pseudoscalar meson theory, with an extended pseudovecto coupling to the nucleon and neglect of nucleon recoil effects, is shown to be capable of explaining the existing data on the $P$-wave pion-nucleon scattering. The required sizes of the source radius and coupling constant correspond to a relatively weak pion-nucleon coupling, but reactive effects in the scattering are nevertheless so important that the lowest order approximation in a perturbation treatment is completely inadequate. The Dancoff approximation, on the other hand, is accurate to within 10 or 20 percent.