Moreover by setting out the being in motion corresponding to each of the two motions (say) and we may argue that the whole being in motion will correspond to the whole motion (for if something else did, there would be more than one being in motion corresponding to the same motion), the argument being the same as that whereby we showed that the motion of a thing is divisible into the motions of the parts of the thing; for if we take the being in motion corresponding to each of the two motions, we shall see that the whole is continuous.