.
Why He Stages the Play.
Hamlet's decision to stage a play in order to "catch the conscience of the King" results from his obsession with gathering information about whether or not Claudius' committed the crime. Why is Hamlet "obsessed" with doing this, as opposed to merely being "interested" in gathering such information? The reason is that whatever Hamlet learns from such information, that is, whether it proves or disproves Claudius' guilt, Hamlet will feel great psychological relief from the information. If he disproves to himself that Claudius killed the king, then Hamlet will be instantly relieved of his obsession to kill Claudius, along with the intense psychological stress it induces within him. At worst, he will still feel the substantial but much more manageable stress he felt, before he met the ghost, from his response to his mother's over-hasty marriage to Claudius. In addition, proving that Claudius is guilty has great psychological advantages for Hamlet. For one thing, such proof will prove to him that his endeavor to kill Claudius is justified. Thus, he will not be engaging in his risky, dangerous undertaking for no reason. Such proof will also spare a principled Hamlet from the agonizing possibility of engaging in a crime that violates many moral, political and religious principles if it is not justified. Such proof will also justify Hamlet's inner maintenance of the painful sense of resentment he feels towards Claudius, Gertrude and others within the royal household. It will also provide Hamlet with the opportunity to use hard evidence to prove to his friends and loved ones that Claudius is guilty. This might make them support Hamlet in his endeavor, thus providing him with the psychological support he needs to carry it out. Thus, disproving the ghost's message promises Hamlet instant relief from his pain, and proving this message will nurture him by enabling him to justify his obsession and to possibly use such proof as a means of acquiring peer support of his endeavor.