D O C . 4 4 3 G E N E R A L R E L AT I V I T Y A N D M O T I O N 4 3 7 Summary If the masses subject to a gravitational field are conceived of as singularities, then the law of motion is completely determined by the field equations.1) If the total field is approximated by the solutions to linearized equations, then the law of mo- tion is given by the geodesic equation. In a later paper, the law of motion of elec- trons, considered as singular points, shall be deduced from the field equations. It is well known that electrically neutral atomistic masses do not occur in nature, and that hence the subject of this paper does not immediately correspond to an ob- ject in nature. However, the advance made here is that it has been shown for the first time that a field theory can contain within itself a theory of the mechanical be- havior of discontinuities. This can become important in the theory of matter, i.e., in quantum theory.[39] 1) In the present paper, this has been fully proven only for the case of equilibrium. [p. 13]