"He that has eyes to see and ears to hear may convince himself that no mortal can keep a secret. If his lips are silent, he chatters with his fingertips; betrayal oozes out of him at every pore..."

--Sigmund Freud

Ah, did you once see Shelley plain,
And did he stop and speak to you
And did you speak to him again?
How strange it seems and new!

But you were living before that,
And also you are living after;
And the memory I started at--
My starting moves your laughter.

--Robert Browning, "Memorabilia"

"The Shelley whose appearance regularly shocks Browning is, of course, a ghost. The bare fact of talking with a ghost is bound to be curious and impressive--enough to make one start. But at the same time it's not unusual to converse with ghosts, and this generalization can be taken beyond the sphere of literature, beyond the notion of writers struggling with the mighty dead for imaginative priority..."

http://www.freud-museum.at/freud/chronolg/1925-e.htm