Claudius knew. That's why he conspired with Laertes to kill Hamlet first.
Hamlet was going to act crazy until he got an opportunity to revenge himself on Claudius. Not much of a plan, really.
I think he was afraid Hamlet was going to find out that Claudius killed Hamlet's father.
Some examples of disorder in Hamlet include: -Disorder in Society -Loss of King Hamlet -New King (Claudius) -Treat of invasion by Fortinbras of Norway -Disorder of Family -Claudius killing his own brother -Incestuous Relationship (Claudius marrying his sister-in-law) -Betrayal -Disorder in the Universe -Ghost -Disorder of the Mind -Hamlet pretending to be crazy -Ophelia going crazy
Hamlet stabbed him right behind the arras in Queen Gertrude's room.
Rosencrantz is (probably only was) a friend of Hamlet. Rosencrantz and Guildenstern (often considered one) spy on Hamlet the whole time for Claudius. They are constantly in between a plot that they have no idea about (Hamlet versus Claudius) and never learn of their real reason for their trip to Denmark. They probably had no idea that they were going to executed either.
Hamlet tells the audience that he does not want to give Claudius the opportunity to absolve himself of all his sins before he dies. He says that to kill Claudius then would mean that Claudius would die a guiltless death, which is exactly what Hamlet did not want. He wanted to avenge his father by killing Claudius in the same way in which Old Hamlet was killed: unprepared and unforgiven for all of his outstanding sins. This is what Hamlet tells the audience, but it is also probably an example of Hamlet's inability to take action. Hamlet is presented with a perfect opportunity to avenge his father, and he comes up with an excuse as to why it is not the right time. The question is whether or not Hamlet is ready to take his life, not whether or not Claudius is going to have a sinless death.
The ghost says that he is stuck in purgatory because he did not have a chance to confess before he died. It would have been less cruel to have killed him as he stepped out of the confessional, but give Claudius some credit here--he's not going to kill Hamlet in such a way that Claudius was going to get caught. Claudius might have chosen a less nasty poison, one supposes. That would have been less cruel.
Mostly it's not so much of a discussion as Hamlet berating her. She thinks that she is going to give him heck for disturbing Claudius, but it soon becomes apparent that the shoe is on the other foot. He goes off into a long rant in which he abuses Claudius to her, and blames her for having anything to do with him. But she does not get angry with him, probably because she is digesting his remark "Almost as bad, dear mother, as kill a king and marry with his brother." At first she demands to know what he is talking about, but from his abuse of Claudius, she figures it out, and makes the connection with the Mousetrap play. She begins to suspect that Hamlet may be right about Claudius murdering Hamlet Senior. Then the ghost of his father appears to Hamlet, and Hamlet's rant is interrupted. Thereafter it is more like a discussion than a dressing down. The following topics are discussed: 1. Whether Hamlet is crazy. 2. Whether Gertrude should suspend conjugal relations with Claudius. 3. Hamlet's imminent trip to England. 4. What Hamlet is going to do with the corpse of Polonius.
As Claudius's advisor, it was Polonius's job to advise him on all matters of state. We presume that Polonius advised Claudius to deal with Fortinbras diplomatically through his uncle the king of Norway. This appears to have been successful. He also advised Claudius that in his opinion Hamlet was suffering from unrequited love for Ophelia and the best way to find out what was going on with Hamlet was to throw everyone Hamlet appears to have cared about at him, including Ophelia, Rosencrantz, Guildenstern and Gertrude, and spy on the conversation. This was not such good advice.
Quite a lot. He respected Laertes, in public at least, and had no evil plans to kill him. Polonius, Laertes' dad, was Claudius' right hand man, and so Claudius had no reason to treat Laertes badly. Conversely, Claudius could never truly see Hamlet through the eyes of a father figure (as he told him he did) because C had killed Hamlet's dad. When the king found out that Hamlet knew about the murder of Hamlet snr., Claudius obviously distanced himself from Hamlet, even sending him to England to be killed.
This line is from Hamlet, Act 2, Scene 2. Prince Hamlet has been told by the ghost of his father, King Hamlet, that Prince Hamlet's uncle, King Claudius, murdered his own brother, King Hamlet. Claudius then married the dead King Hamlet's wife and Prince Hamlet's mother, Queen Gertrude. Since Hamlet does not know if the ghost is truly his father and telling the truth, he devises a plan that he believes will prove if what the ghost has said is true. Actors have come to perform at Elsinore Castle for King Claudius and Queen Gertrude. Hamlet asks them to use his altered version of the play, in order to "catch the conscience of the King." The alteration tells the story of a Queen whose husband is murdered by poison. The poisoner then woos the Queen with gifts. Though she rejects him for awhile, in the end she accepts his love. Hamlet plans to watch Claudius' reaction to the altered portion of the play, and discern from that response if Claudius is guilty. His fear of King Claudius' power, and his desire to shame his mother, Queen Gertrude, is the reason for Hamlet's indirect method of accusing the King. If Hamlet's plan doesn't work, he will still be free to pursue other possibilities.
"As for your intent in going back to school in Wittenberg, it is most retrograde to our desire." Act I Scene 2.