I'm currently working on writing an essay on William Shakespeare's Hamlet. My thesis is "By considering Hamlet's antic disposition, it can be argued that his guise reflects his reality." I need help finding "textual elements" that support my thesis and understanding what exactly textual elements are.
The phrase "textual elements" is simply literary theory jargon for specific pieces of evidence in play, either in the form of quotations or other elements of the actually wording of the play such as stylistic devices.
Thus if you wanted to prove that Hamlet's pretense of madness is not actually a pretense, but rather a revelation of an inner disturbed reality, you might use quotations from before he starts pretending to be mad or soliloquies, to show that many of the same characteristics found in his pretense of madness are actually part of his normal character.
It should be noted that the theme of madness and sanity is actually fairly common in revenge tragedy; the most striking phrasing, I think, is actually in The Revenger's Tragedy, where the protagonist Vindice says:
Surely we're all mad people, and they
Whom we think are, are not — we mistake those:
'Tis we are mad in sense, they but in clothes.
In the case of Hamlet, you might argue that when he is sane, he is melancholy almost to a point that would appear clinically depressed, but when he is mad, his statements, though on the surface appearing irrational, usually have quite pointed, logical double meanings. Also, while pretending madness, Hamlet acts much more cleverly and with greater purpose than he does while putatively sane. Thus there is a sense that Hamlet becomes saner as he feigns insanity.