The Hollow Men

Squier asks Gabby towards the end of Act I if she's read "The Hollow Men" (p. 29). When she indicates that she hasn't, he says "Don't. It's discouraging."

"The Hollow Men," is a poem by T. S. Eliot that shares many of the common features of his more famous poem, "The Waste Land."  Although it is much shorter and pre-dates TWL it does require footnotes/hypertext to understand the ample allusions -- a good version can be found here.  The poem ends:

This is the way the world ends
This is the way the world ends
This is the way the world ends
Not with a bang but a whimper.

Eliot was responding to the absolute failing of rationalization and human progress by the specter of World War I:  All of the progress of the Western world had ended in ugly trench warfare, suffering, and death.

N.B.: "The Hollow Men" has also been heard by Chicago audiences before -- when it was quoted at the end of Tracy Letts's August:  Osage County at Steppenwolf in 2007.