Kant’s two cosmological starting points—dynamic stretch into the void in the 1740s, and homogeneous material chaos in the 1750s—are not contradictory. The reflections in his first book begin with the very beginning, with existence prior to extension. The reflections in his second book proceed from the next stage, existence in extension. Kant’s initial cosmogony starts with force stretching out into a void, creating a field. His next theory begins with the extended field sedimenting into a scattering of particles. He does not replace a dynamic by an atomistic theory, or switch from active forces to inert matter. Matter always remains the guise and result of energetic interactions. As he would stress in his professorial thesis, the Physical Monadology (1756), particles are force concentrations, whose solidity is due to dynamic interplay.