Building on his earlier works, Kant continues to expound that force is prior to extension; everything comes about through the dynamics of force, pushes and pulls; and even on the smallest scale the attractive-repulsive interplay must structure space (determinata volumina, 1:484.10–12). Bodies are coherent webs of force-points. The dynamic point-entities are intelligible as mathematical centers, but dynamically, they are centers of active radiation fields that mutually confine each other. Physical monads are thus elementary energy spheres (sphaera activatis or ambitum activitatis; 1:481.9–10, 37). They are points and, as such, indivisible—but they radiate and in doing so create extension. Hence non-extended points constitute extended composites. We must think in dynamic terms, because corpuscular interpretations of nature do not work, not even for the ether (1:486.5–35). As he writes at the end of the Physical Monadology, the ether is energetically structured space or “fire matter” (aether seu materia ignis; 1:487.18), woven by elastic bonds (iunctae elasticitates; 1:487.12).