In Shakespeare's play, Hamlet, what is Shakespeare saying about the theme appearance vs. reality?

Shakespeare's takes a serious look at the theme of
"appearance vs reality." This theme is a common occurrence in life; in this story,
Shakespeare demonstrates his belief that such behavior can have deadly
results.

"Appearance vs reality" is seen when the King
andencourageto pull himself together regarding Old Hamlet's death. Gertrude asks why his
mourning seems to be so difficult. He responds that it is not something
that "seems:" what she sees is real,
not just for show. Hamlet defies the idea that his actions are
anything but as they appear.

QUEEN GERTRUDE

...Thou know'st 'tis
common; all that lives must die,

Passing through nature to
eternity.

HAMLET

Ay, madam,
it is common.

QUEEN GERTRUDE

If it be,

Why seems it so particular with thee?

HAMLET

Seems, madam! nay it is; I know
not 'seems.'

'Tis not alone my inky cloak, good mother,

Nor customary suits of solemn black,

Nor windy suspiration of forced
breath,

No, nor the fruitful river in the eye,

Nor the
dejected 'havior of the visage,