I do not set my life at a pin’s fee;
And set my soul, what can it do to that,
Being a thing immortal as itself?

– William Shakespeare

Hamlet, Act 1, Scene 4. When the Ghost beckons Hamlet to follow, Horatio and Marcellus try to stop him, urging him not to go. But in this passage, a melancholic and grieving prince says that he doesn’t value his life at the price of a pin. So he doesn’t see a reason to fear the Ghost.