"That it should come to this!" (Act I, Scene II)
What does it mean? Just after speaking to his mother Gertrude and uncle (and step-father) King Claudius, Hamlet has his first of five soliloquies. When Hamlet exclaims, "[t]hat it should come to this," he'd just finished describing how the world has gone to fodder. Then Hamlet goes on to say how he cannot believe his mother would marry his father's brother (i.e., Hamlet's uncle). This quote shows Hamlet's fury and shock at his mother's remarriage. In Hamlet's mind, the world is in chaos and the remarriage is the apex of things spiraling out of control. Soliloquies allow the audience to see into a character's inner thoughts. The soliloquy as a whole belays the reasons for Hamlet's initial deep melancholy and confusion that persists for much of the play.
"Frailty, thy name is woman!" (Act I, Scene II)
What does it mean? Hamlet is still speaking in his first of five soliloquies. The "woman" he specifically refers to is his mother. Hamlet felt she was weak, or not strong enough to mourn his father longer. Hamlet goes on further to say that not even an animal or beast, who has no reasoning skills, would have abandoned the mourning so quickly. All in all, this shows how angry and confused Hamlet is by his mother's remarriage.
"Neither a borrower nor a lender be; For loan oft loses both itself and friend, and borrowing dulls the edge of husbandry." (Act I, Scene III)
What does it mean? Here Polonius is giving his son, Laertes, sound advice before Laertes returns to Paris. Polonius is really saying loaning money to other people is dangerous. Often, people don't pay you back and you use a friend because of the failed transaction. On the flip side, it is distasteful to borrow money because it is impolite and usually indicates you are living outside of your means.
"This above all: to thine own self be true." (Act I, Scene III)
What does it mean? Again, Polonius is doling out sage advice to his son, Laertes. Simply put, Polonius is telling his son "be yourself." In the context of the play, Polonius is also telling Laertes to be a gentleman and not "false to any man" (line 80). Overall, Polonius's advice helps reveals a theme of irony that threads throughout the play. Neither Polonius nor Laertes heeds the advice that Polonius gives in this scene, and both perish due to their lack of adherence.
"Something is rotten in the state of Denmark." (Act I, Scene IV)
What does it mean? At the end of Scene IV, a guard, Marcellus, says these famous words to Horatio. After Hamlet follows the ghost, Marcellus and Horatio know they have to follow as well, because Hamlet is acting so impulsively. Marcellus's words are remarking on how something evil and vile is afoot. This moment could be interpreted as foreshadowing of the impending deaths of most of the principle characters.
"Though this be madness, yet there is method in't." (Act II, Scene II)
What does it mean? At this point of the play, Hamlet and Polonius are interacting onstage, but this quote is technically spoken by Polonius to the audience, in an aside. What Polonius is saying is that, even though Hamlet is talking crazy, it actually makes sense, or it has a "method." Polonius's assertion is ironic because he is right and wrong. Polonius believes Hamlet is acting "mad" because Hamlet's love of Ophelia has driven him to such. While Polonius is correct to think that there is reason behind Hamlet's actions, he is incorrect as to the cause. Hamlet is purposefully acting mad to disguise his true mission to avenge his father's murder.
"To be, or not to be: that is the question." (Act III, Scene I)
What does it mean? As one of Shakespeare's all-time famous quotes, Hamlet's words have stood the test of time and are often quoted even today in both academia and pop culture. In the beginning of his fourth, and best known, soliloquy Hamlet muses about the conundrum of suicide. He wonders if one route is "nobler" than the next. At this point in the play, Hamlet has been unable to act upon his motives for personal revenge, and this frustrates him. Which is better, suffering as he has been or ending it all? The tone of Hamlet's soliloquy is more meditative than angry, but he does seriously consider suicide. He relates his personal struggle to the struggles that all of mankind shares. Given that you don't know what happens after you die, Hamlet realizes that death wouldn't be the ideal escape he craves.
"The lady doth protest too much, methinks." (Act III, Scene II)
What does it mean? Hamlet's mother, Queen Gertrude, says this famous line while watching The Mousetrap. Gertrude is talking about the queen in the play. She feels that the play-queen seems insincere because she repeats so dramatically that she'll never remarry due to her undying love of her husband. The play-queen, in fact, does remarry. It is unclear whether Gertrude recognizes the parallel between herself and the play-queen; Hamlet certainly feels that way. This moment has an irony that is shown throughout the play.