ABSTRACT
This chapter adopts a naive attitude towards Newton’s Laws of motion. The first law of motion is regarded sometimes as a definition of equal times. This view is radically absurd. In the first place, equal times have no definition except as times whose magnitude is the same. In the second place, unless the first law told us when there is no acceleration (which it does not do), it would not enable us to discover what motions are uniform. In the third place, if it is always significant to say that a given motion is uniform, there can be no motion by which uniformity is defined. The second and third laws introduce the new idea of mass; the third also gives one respect in which acceleration depends upon configuration. The laws of motion, to conclude, have no vestige of self-evidence; on the contrary, they contradict the form of causality which has usually been considered evident.
