But this equation has itself received the form that it has by presupposing the explanation given for the resulting terms by means of analysis; this presupposition is that the uniformly accelerating motion is composed of a formally uniform motion continued with the velocity attained in the preceding period of time, and of an increment (the a in a ie the empirical coefficient) which is ascribed to the force of gravity a distinction which has absolutely no concrete existence or foundation in the nature of the matter itself, but is only the expression, in false physical form, of the results of the assumed analytical treatment.