Critics and literary historians do not agree on what constitutes literary Expressionism, or even if it was a movement. For example, in R. S. Furness's book Expressionism, he acknowledges the attempts others have made to trace the origin of the movement back to the eighteenth century's Sturm and Drang, but claims, "It can also be argued that Expressionism is simply the name given to that form which modernism took in Germany." Roy Allen calls the problem faced by literary historians in trying to define literary Expressionism a "bugbear." Other critics and literary historians are more confident in their assessment. Ernst Toller, who is considered one of the leading postwar expressionist playwrights, writes of the movement, as embodied in drama: "Expressionism wanted to be a product of the time and react to it. And that much it certainly succeeded in doing." Mark Ritter points out, in "The...