Recent work by Sattinger has shown that General Relativity is relevant for general fields that include both gravitational and electrostatic fields. Einstein developed the theory of general relativity based on the idea that "gravitation occupies an exceptional position with regard to the other forces" and states that the "….. gravitational field at the same time define the metrical properties of the space measured". The mathematical arguments used however could be as readily applied to any force field including those of electromagnetic nature. Interestingly, Einstein then spent much of his later years engaged in trying to develop a unified field theory. Much of the confusion regarding the general applicability of can be attributed to comments by Maxwell who suggested that the equations for electromagnetism, now known as Maxwell's Equations, could not be applied to gravitation as it would lead to infinitely negative potentials.