Symbolism, Imagery, Allegory

In English class, Andy's class has been reading Macbeth, so their teacher asks them what they all think of it. Together, they read a quote from the play:

And all our yesterdays have lighted fools
The way to dusty death. Out, out, brief candle!
Life's but a walking shadow, a poor player
That struts and frets his hour upon the stage
(23.12)

This quote is about the darkness of life, and the class decides it means that life is no longer meaningful in any way. In fact, when the teacher asks them what Macbeth means, B.J. answers by saying:

Life is short, and then you die. And on top of that, life don't really mean nothin' anyway. But I think the only reason that he was so depressed was because he had been the cause of so much death that he couldn't find nothin' else good about livin'. (23.14)

Sound like anyone you know? Yeah… it sounds a whole lot like Andy. Andy, like Macbeth, kills his friend. Unlike Macbeth, though, Andy does it by accident instead of to become king. Unfortunately, though, this difference is completely lost on Andy, and instead he sees himself as being just as terrible as Macbeth is. In this way, Macbeth becomes a symbol for just how terrible Andy believes himself to be—and, because of this, a reminder of how misguided Andy is in this assessment.