German idealism
Few 20th-century philosophers embraced the core tenets of German idealism after the demise of British idealism. However, quite a few have embraced Hegelian dialectic, most notably Frankfurt School critical theorists, Alexandre Kojève, Jean-Paul Sartre (in his "Critique of Dialectical Reason"), and Slavoj Žižek. A central theme of German idealism, the legitimacy of Kant's "Copernican revolution", remains an important point of contention in 21st-century post-continental philosophy.