An idea, like a ghost (according to the common notion of ghosts), must be spoken to a little before it will explain itself. – Attributed to Dickens in Many Thoughts of Many Minds by Henry Southgate, 1862

He stood looking after them… as though he had perceived that they had come back accompanied by a ghost a-piece. – Charles Dickens, Little Dorrit

Whatever its origin, a belief in spirits seems to have been common to all the nations of the ancient world who have left us any record of themselves. Ghosts began to walk early, and are walking still, in spite of the shrill cock-crow of wir haben ja aufgeklärt. – James Russell Lowell, “Witchcraft”

A house is never still in darkness to those who listen intently; there is a whispering in distant chambers, an unearthly hand presses the snib of the window, the latch rises. Ghosts were created when the first man woke in the night. – J.M. Barrie, The Little Minister, 1891