From Who Knows Who Knows Who’s There? An Epistemology of Hamlet (Or, What Happens in the Mousetrap): Basically, Roth seizes on Hamlet calling Lucianus "nephew to the King", so Lucianus' murder of the King is seen as Hamlet threatening Claudius' life. He proposes that Hamlet knows that Claudius may have reacted to this perceived threat and not out of overwhelming guilt, so The Mousetrap doesn't actually give Hamlet any more reason to think that Claudius did in fact kill King Hamlet. If anyone wants to read the article, let me know what you think. I'll hold most of my comments for now and just say that my major problems are with Roth's suggestions about what Hamlet knows or thinks.