The static dispersion relations for the $S$-wave $\pi -\Lambda$ and $\pi -\Sigma$ scattering amplitudes are investigated under the assumptions that the dominant forces result from a scalar $\pi \Lambda \Sigma$ interaction, and that multiple meson processes may be ignored. If it is required that the $\pi -\Lambda$ effective range is small, or alternately, that no subtractions be made in the dispersion relation for the denominator function of the $\pi -\Lambda$ amplitude, the $\pi \Lambda \Sigma$ coupling constant is determined to be $F^2\sim 1.6$. However, such a strong interaction leads to an attractive force in the isotopic-spin 2, $\pi +\Sigma$ $S$ state that is more than sufficient to produce a bound state. A brief discussion is given of the meaning of this result, and of a possible related mechanism for the 1380-Mev $\pi -\Lambda$ resonance.

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