Which theme is reinforced in the excerpt below from Shakespeare's Hamlet?

Rightly to be great
Is not to stir without great argument,
But greatly to find quarrel in a straw
When honor's at the stake. How stand I, then,
That have a father kill'd, a mother stain'd,
Excitements of my reason and my blood,
And let all sleep[?]

>>appearance versus reality

>>complexity of action

>>impossibility of certainty

>>mystery of death