Neutral Centers are triune in their dynamical natures possessing harmonic, enharmonic and dominant forces. Three such centers considered together are One Center having a triune nature - Positive, negative and neutral. These three states are constantly interchanging state of concord and discord reciprocally thus maintaining unition or concordance to center. See Hull's Quadrature of the Circle
A harmonic center determines a circular orbit but an elliptical orbit requires three non-coincident centers.