This speech in Hamlet is spoken, of course, by Hamlet after the Player King has delivered his moving monologue about Hecuba. Thisis an ancient tale, and, while it'sa tragic story, the characters and events of this story are nothing personal to the actor. Still, the Player King is moved to tears as he tells the story. Hamlet's speech which follows is generally known as the "rogue and peasant slave" soliloquy. In it, Hamlet has two key themes. First, he berates himself for his comparative lack of emotion even for a just and personal cause and is amazed at the actor's ability to create such emotion for something totally disconnected from his life. He says:
O, what a rogue and peasant slave am I!
Is it not monstrous that this player here,
But in a fiction, in a dream of passion,
Could force his soul so to his own conceit
That from her working all his visage wann'd,
Tears in his eyes, distraction in's aspect,
A broken voice, and his whole function suiting
With forms to his conceit? and all for nothing!
What's Hecuba to him, or he to Hecuba,
That he should weep for her?
Next, Hamlet notes that if this actor had half the reason, the "motive and cue for passion," that he did, he would be a rather wild man on stage, confounding all with his emotions and actions. Yet, Hamlet says, he "can say nothing"--not even against a king who has usurped the throne by killing his own brother. He says he deserves all insults of word and deed for this lack of resolve and passion. He continues his diatribe against himself:
Why, what an ass am I! This is most brave,
That I, the son of a dear father murder'd,
Prompted to my revenge by heaven and hell,
Must, like a whore, unpack my heart with words,
And fall a-cursing, like a very drab,
Then comes the second portion of this soliloquy in which Hamlet makes a plan. "About, my brain!" he says, and then he determines to reaffirm the King's guilt by enacting a play within a play (within a play, actually)--inserting a few lines into the play in order to catch the King off guard and ensure himself of Claudius's guilt.
I'll have these players
Play something like the murder of my father
Before mine uncle: I'll observe his looks;
I'll tent him to the quick: if he but blench,
I know my course.
In the end, Hamlet has--once again--made a plan to determine once and for all:
...the play 's the thing
Wherein I'll catch the conscience of the king.