Fig. 1 above shows a conducting line that could be neural conductor.      v = voltage                      i = current      x = position along the line              alpha= arbitrary length interval      R = resistance/length                     L=electromagnetic inductance/length      G= membrane leakage conductance/length               C=capacitance/length Fig. 1 above shows an arbitrarily chosen length alpha, of arbitrary magnitude, which we will call delta x.   R, L, G, and C are natural law operators. To derive line differential equations in dv/dx and di/dx, we first need finite difference equations, (delta v)/(delta x) and (delta i)/(delta x).