What theme or meaning do you think Samuel Beckett was trying to convey in his play Waiting for Godot? (He doesn't seem to propagate anything, but has left it open to interpretation?)
I also agree with #6 and I would add that, in absurdist theater, there will always be leadway for the audience to provide its own interpretation of the play. That is, ultimately, what the absurdist dramatist aims to achieve: That subtle connection between the "nothingness" of the plot and the inner sanctum of the reader's emotion. In the end the play will achieve its duty if it leaves the public asking more questions than what it can offer. The audience will be the final judges of what playwright is trying to convey in his work. It is almost like a piece of art work for which many people have several differently interpretations and opinions.
Since Beckett himself was rather reticent about the meaning of the play, perhaps its appeal has been the opportunity for interpretation. As it was written in the wake of World War II, there does seem reflected in this play the nihilism of this period. All that the characters have is themselves and they must create some order as the wait for good or whatever is to come.
I think that actually one of the fascinating aspects about this play is the very bleak and rather disturbing view of the world that is presented to us in Beckett's absurdist creation. Life is condensed down into absolutely nothing and only the friendship between Vladimir and Estragon is able to stave off temporarily the loneliness of such a barren existence.
I like to read this play as an existentialist romp through the difficulties of adhering to values which are constructs as opposed to truths.
Everything in the play is arbitrary and contingent upon an absent figure. This absent figure gives purpose and meaning to the action and characters of the play, but only on the thinnest and most insignificant level.
Beckett repeatedly, sometimes with great frustration, denied that there was much of an agenda or deeper meaning in Waiting for Godot. Some people have interpreted it as an allegory of the Cold War, others the German occupation of France, still others have read into it some psychological meanings. I think that it is intended to be absurdist, without much deeper meaning, and that it should be understood that way.