Existentialism − why are we here? Why should Rosencrantz and Guildenstern do anything unless someone asks them to? They find themselves as pawns in a gigantic game of chess, yet make no effort whatsoever to escape.
Free will vs. determinism − is it their choice to perform actions, or are they fated to live the way they do? The implication the play gives is that it does not matter what choices Rosencrantz and Guildenstern make, they are trapped within the logic of the play, and cannot escape, being fated to follow a destiny determined by the plot. Hamlet ends with the news of their deaths, so they have to die.
Search for value − what is important? What is not? Does anything matter? If we are all going to die, why do we continue to live?
Futility of language − Do words always mean what we say they mean? How do we know what words with multiple meanings mean? Why do words mean what they mean? How do we interpret what is being said to something sensible when it is not? How do words determine madness?
The impossibility of certainty.
These themes, and the presence of two central characters that almost appear to be two halves of a single character, are shared with Samuel Beckett’s Waiting for Godot and the two plays are often compared. Many plot features are similar as well. The characters pass time by playing Questions, impersonating other characters, and interrupting each other or remaining silent for long periods of time. Other authors have also experimented with characters who (partially) understand that they are fictional − for example, in Frank Baker’s classic Miss Hargreaves: A Fantasy, in Jostein Gaarder’s Sophie’s World, in Robert Shea and Robert Anton Wilson’s Illuminatus! trilogy, in Luigi Pirandello’s Six Characters in Search of an Author, and in Paul Wühr’s Das falsche Buch. Jasper Fforde’s Thursday Next series also makes heavy use of characters who understand that they are fictional.