Shortly after the death of Maupertuis, the president of the Academy of Berlin, Mr. Gleditsch, the curator of natural history, was traversing the hall in solitude, when he saw the phantom of the president standing in an angle of the room with his eyes intensely fixed on him: an effect perfectly explicable by the association of intense impression of memory in the very arena of the president’s former dignity.
You will remember the story of a rich libertine, told by Sir Walter Scott. Whenever he was alone in his drawing-room, he was so haunted by a spectral _corps de ballet_, that the very furniture was, as it were, converted into phantoms. To release himself from this unwelcome intrusion he retired to his country house, and here, for a while, he obtained the quiet which he sought. But it chanced that the furniture of his town house was sent to him in the country, and on the instant that his eyes fell on his drawing-room chairs and tables, the illusion came afresh on his mind. By the influence of association the green figurantes came frisking and capering into his room, shouting in his unwilling ears, “Here we are! here we are!”
It is not, however, essential that there be substance at all to excite these spectres. _Idea_ alone is sufficient.
Do you think it strange that a ghost should appear fleshless and shadowy without some supernatural influence? Be assured that the only influence exists in the sublime and intricate workings of that mind which in its pure state was itself an emanation from the Deity; which is only shadowed by illusion while in its earthly union with the brain, and which, on the dissolution of that brain, will again live uncombined, a changeless and eternal spirit.
It is as easy to believe the power of mind in conjuring up a spectre as in entertaining a simple thought: it is not strange that this thought may appear _embodied_, especially if the external senses be shut: if we think of a distant friend, do we not _see_ a form in our mind’s eye, and if this idea be intensely defined, does it not become a phantom?
“Phantasma est sentiendi actus, neque differt a sensione aliter quam fieri differt a factum esse.”
You have dipped deeply into Hobbes, Astrophel, and will correct me if I misquote this philosopher of Malmsbury.