For the first 2,000 years of theatrical (not counting pre-history imitation of an action), Theatre had its own language, largely based on metaphor and metonymy. A soldier’s uniform and weapons stood for the mass of the army; a space stood for a field, a drape stood for a wall, etc. The audience read this “language” easily, with the help of the dialogue. By the 19th century the stage scenery had become a “wing and drop” set—painted two-dimensional representations of three dimensions. When realistic drama (the staging of real-life conflicts and social imbalances) replaced romantic and classical dramas, a new approach to staging was required—it was called “the teacup school”, because the actors no longer had to mime props, fireplace mantles, etc., but used real teacups, etc. on stage. The language of stage performance changed to a “fourth-wall” mentality, in which the audience was inveighed to imagine a real room with an invisible wall through which the audience member (sometimes called the “witness”) could watch and hear an actual real-life event. Thus, in the late 19th-early 20 century, Ibsen, Chekhov, etc. not only wrote about actual “drama” between real, believable characters, but also called for real furniture, props, etc, to stage their dramas.