Also, some occur elsewhere, such as the Bible, or are proverbial. A few, listed out (Note: all are second quarto except as noted):
Act I, scene 1:
As the mote is to trouble the mind's eye ("Mind's eye," though it did not originate as a phrase in this play, was popularized by Shakespeare's use of it.[1])
And to the manner born, ... (i.e., predisposed to the practice. This phrase is sometimes mistakenly rendered as "to the manor born", and used to mean 'of the privileged class”; see references for more on this one. In recent years this misconception has spread through the popularity of the British sitcom To the Manor Born, the title of which was a deliberate pun on Shakespeare's phrase.)
More honoured in the breach than the observance. (Another misunderstood phrase, in the context (the Danes' drinking customs) it signifies that the Danes gain more honour by neglecting their drunken customs than following them; however, it has come to be used in situations where it simply means that a custom is hardly ever followed.)
O, answer me! (Hamlet's anguished cry to his father's ghost)
Alas, poor Yorick! I knew him, Horatio (the Horatio is often replaced with the word well, a common misquote; in the previous scene Laertes observes, "I know him well...")
Let Hercules himself do what he may,
The cat will mew and dog will have his day.
Will he nill he.
Act V, Scene 2:
There's a divinity that shapes our ends,
Rough-hew them how we will ...
report me and my cause aright ... To tell my story. (Hamlet's dying request to Horatio)
... The rest is silence. (Hamlet's last words)
Now cracks a noble heart. Good night, sweet prince,
And flights of angels sing thee to thy rest.
...so shall you hear
Of carnal, bloody, and unnatural acts,
Of accidental judgments, casual slaughters,
Of deaths put on by cunning and forced cause, (Horatio's discussion of the play's blood-bath)