What does Eugene O'Neill mean to say about dreams in the play? I'm wondering if he's referencing the dreams of his characters or the dreams of humans in everyday life.
O'Neill is making a universal point about dreams and the power they have over us. It's not just the regular habitués of Harry Hope's saloon who dream their lives away; many of us in the world outside do too. To that extent, one can see the play's colorful cast of characters as a microcosm of the world in which they and we both live.
Everyone has dreams, and that's perfectly healthy and normal. But all too often they can turn into debilitating delusions, which prevent us from facing up to the realities of life. That's the condition in which Harry Hope's customers find themselves and from which Hickey wants to liberate them. But in due course even Hickey comes to realize that some people need their dreams—even utterly delusional ones—to keep them going through life's various trials and tribulations. The general point that O'Neill seems to be making here is that dreams are not just an optional extra but an essential part of what it means to be human.
Eugene’s commentary about the elusive and illusive nature of dreams applies to his characters and people in real life. In the play, the idea of the American dream is presented as a paradoxical idea: hope in the unobtainable. Each character in Hope’s bar has become or always was a failure, at least in terms of material success. Most of them see their failure as a result of individual shortcomings. The commentary on real life, during O’Neil’s own time is that the American Dream exists but not in the sense that it is for everyone. And the further commentary is that it is not just based on individual shortcomings. While the system in America makes it easier for some to achieve their dreams, overthrowing the system will still result in a flawed system precluding others from their pipe dreams. At the time, communism and socialism were scorned by the majority but embraced by a minority who felt this was a better system for equality. The elusiveness of the American Dream was tied directly to social inequality.