Read the exchange between Hamlet and Claudius in Act IV.
Ham.
A man may fish with the worm that hath eat of a king, and eat of the fish that hath fed of that worm.
King
What dost thou mean by this?
Ham.
Nothing but to show you how a king may go a progress through the guts of a beggar.
What point does Hamlet seem to be making in this exchange?

You never know what you may be eating.

A beggar is as good of a fisherman as a king.

Death reduces everyone, even kings, to worm food.

A fish is not particular about the worms it eats.