Interesting Hamlet Allusion

After seeing Liz's post about the Hamlet scene in Freaky Friday, I looked up more pop culture references to Hamlet, and I found a particularly interesting one. Within the first page of A Christmas Carol, Dickens writes the following: "Here is no doubt that Marley was dead. This must be distinctly understood, or nothing wonderful can come of the story I am going to relate. If we were not perfectly convinced that Hamlet's Father died before the play began, there would be nothing more remarkable in his taking a stroll at night, in an easterly wind, upon his own ramparts, than there would be in any other middle-aged gentleman rashly turning out after dark in a breezy spot – say Saint Paul's Churchyard for instance – literally to astonish his son's weak mind." This quote appears within the first page of the novel and is important because it sets a strong foundation for the plot of the novel. Marley has to be dead or else Stooge would not be left alone and Marley's ghost could not be used to haunt Stooge. The plot wouldn't work if Marley's death didn't occur. This applies to Hamlet as well. If Hamlet's father were still alive, then none of the events in the novel would have occurred and his ghost wouldn't make sense. This ties into the big question regarding Hamlet's insanity. Is Hamlet actually seeing his father's apparition or is it all a figment of his imagination? What if his father isn't even dead and he's just delusional? However, for the play to make sense, we have to trust in Hamlet and the other characters of the play that Hamlet's father is dead. Regardless, I thought this allusion to Hamlet was pretty cool and pertains to our discussions of Hamlet as well.