I'm not a big fan of this play. The monologues go on and on (and on). I've also never been blown away by the philosophical message. It's hard to tell whether we're really experiencing life or whether we're dreaming? Well, yeah. Maybe it's just because the reality/dream division is something I've batted around in my head since I was a kid--I always used to think to myself, "What if I'm sleeping and my whole life so far has been a dream?--but I just don't feel anything profound in the message.
This gets thrown into every survey of theatre class when it's time to talk about the Spanish Golden Age, but I actually prefer Lope de Vega. Sorry, Calderon.