Carl Philipp Gottfried von Clausewitz, was a Prussian soldier and German military theorist who stressed the moral and political aspects of war. His most notable work, Vom Kriege (On War), was unfinished at his death. Von Clausewitz espoused a romantic conception of warfare, though he also had at least one foot planted firmly in the more rationalist ideas of the European Enlightenment. He stressed the dialectic of how opposite factors interact, and noting how unexpected new developments unfolding under the "fog of war" called for rapid decisions by alert commanders. Clausewitz saw history as a complex check on abstractions that did not accord with experience.