What does Hamlet learn from the Ghost's speech?Act 1

In Hamlet Act I, Hamlet learns the following from the Ghost:

• There is an afterlife.  He's not sure if the Ghost is a demon or a soul trapped in Purgatory, but he's definitely from some supernatural world.


• Hamlet's father was murdered by his brother.

Sleeping within my orchard,
My custom always of the afternoon,
Upon my secure hour thy uncle stole,
With juice of cursed hebenon in a vial,
And in the porches of my ears did pour
The leperous distilment;

• Hamlet's mother was adulterous and incestuous.  She had an affair with Claudius before the marriage.


• Hamlet must revenge his father by killing his uncle:

Avenge me.

Let not the royal bed of Denmark be
A couch for luxury and damned incest.

• Hamlet's mother must be "left to heaven."  Hamlet must not take revenge on his mother.


• Hamlet's father loved Hamlet very much.


• Denmark is a prison.  The entire state is wronged by these vile acts: "the whole ear of Denmark Is by a forged process of my death Rankly abused:"


• Hamlet must listen to the Ghost and all of Denmark hereafter for clues: "List!  List! O List!" and "Now, Hamlet, hear"