Cosmic action turns on gravitation, the reciprocal attraction of masses. When drawn together, masses collide, crash, and are laterally deflected. The angular momentum of deflections generates a counterforce to centripetal gravitation—centrifugal repulsion. Applying Newton to the bond, in his second book Universal Natural History and Theory of the Sky (1755), Kant sees that the dynamics of force, its push and pull, are attraction and repulsion. Matter is then all you need, he says, and you can start building a world (1:229.10–11).