"Knowledge kills action; action requires the veil of illusion; that is the doctrine of Hamlet...Not reflection, no -- true knowledge, an insight into the horrible truth, outweighs any motive for action" --Nietzche (The Birth of Tragedy).
Did Nietzche get it right?
In thinking about this question, it occurred to me that the director of the theatre/acting program that I'm taking classes from, Ron Hufham, said something very recently that made a lot of sense to me with regards to "Hamlet":
"Olivier (Lawrence) said the play was about a man who could not make up his mind. Poppycock! In a four thousand line play, only 252 lines pass between the King's betrayal of his guilt and Hamlet's killing the concealed eavesdropping Polonius in the Queen's bedroom, thinking he was the King."
I don't believe Hamlet's knowledge of the truth about his father's death killed action. I do believe he is a thinker, so he is going to spend a great deal of his time thinking, speaking his soliloquies, berating himself for his slowness to act, but when it gets right down to it, he did act...he just, unfortunately, got Polonius instead of Claudius.
I also don't believe Nietzche was right, overall, in what he said (quoted in Jamie's question). "...true knowledge,..., outweighs any motive for action" - WHAT? True knowledge is what makes Hamlet take that sword and ram it through the arras. True knowledge is what makes him switch the death sentence papers and make sure R&G are executed in his stead. True knowledge is the driving force behind Hamlet's actions from the time Daddy Ghost visits him until Horatio says, "Goodnight, sweet prince."
I don't know how I feel either, I don't think that knowledge kills action in most cases, in fact I think the reverse might be true (but then I don't agree with most of what Nietzsche poses). I think that knowledge is often times the vehicle that drives Hamlet. Hamlet gets some key knowledge as to the actual cause of death of his father the King and it is this knowledge of the "horrible truth" that drives Hamlet to avenge his father's death. I'm not sure that his knowledge of the truth killed his motive to return to Claudius the sentence of death Claudius delivered to his own father. I feel that the truth simply solidified what Hamlet wanted to do all along and drove him toward it the remainder of the play.
I don't know if I agree entirely. Laertes had knowledge, and he acted almost immediately. Hamlet, born and bred to be a Prince of Denmark, has been taught to think before he acts. He just thinks a lot longer than most readers have patience to endure.