The audience encounters a new character along the story, Pozzo. Vladimir and Estragon beign to have a conversation with him; during this time they both tell one another that they must go; leave. The reply to this is always "We are waiting for Godot". Several times, they decide to leave, but one always remembers that they must wait. They raise hope in one another and when it dies out in Vladimir of estragon, the other is sure to mention what exactly their purpose is.
As the paly progresses several other incidents occur, which establish that hope is the central theme. On one occassion the audience can clearly see just how dependent Vladimir and Estragon are on one another because they give each other hope. "Then why do you always come crawling back?"Vladimir asks this question from Estragon, which he reply's with " I don't know".
Near the end, Estragon proposes the idea that they hang themselves, "why don't we hang ourselves", but they settle upon hangning themselves tomorrow, when Godot arrives. It is evident that both Estragon and Vladimir rely on each other for hope
Therefore this makes the central theme, hope. Neither Vladimir nor Estragon would be able to show hope to the reader, if it wasn't for the other. The theme, hope, surely shines through, because they...