 However, while a doctrine of pure, universal laws makes possible a coherent theory of the concept of humanity, Cohen thinks the laws of any actual state will fall short of pure law’s ideal form. He maintains that states, in the course of their development through history, tend to amend their laws so as to better approximate the ideal laws. Cohen does not argue from some antecedent philosophical theory of human nature that history is somehow compelled to exhibit this progress (Cohen 1902, 37). Rather, he simply accepts it as a datum of history: philosophy can no more deny this progress than it can deny progress in the history of physics and mathematics. At the same time, Cohen’s optimism was tempered by an awareness of injustice in the non-ideal world: moral progress must be unending, precisely because no actual state will ever realize the ideal completely (Schwarzschild 1979, 139–40). During the World War, Cohen even came to believe that certain forms of nationalism might be ineliminable engines of humanity’s historical progress towards a cosmopolitan confederation of ideal states. (See Vatter 2017 for discussion of the tension between Cohen’s liberal cosmopolitanism and his wartime nationalism.) There is, in Cohen’s terms, an unbridgeable gap between Being and the Ought.