Let us inquire into the origin of those ghosts in which many civilized people firmly believe! Take away the absurd white sheet, and the human form with which the simple superstition of the peasantry invest them, and you will find in ghosts the idea of communication between the souls of the dead and the living, you will find the thought which we are endeavouring to put before you in a scientific form. This popular notion about ghosts has extended to persons who appear to be educated and enlightened, but who are, in reality, as ignorant in matters of philosophy as the simple peasants, and who are, in addition, addicted to mysticism, which obscures their reason. We allude to _spiritualists_. The term _spiritualists_ is applied to the partisans of a new superstition which sprung up in America and Europe in 1855, as a result of the moral malady of _table-turning_. These good people imagine that they can, by their will, and according to their fancy, cause the souls of the dead, of great men, or of their own relatives and friends, to descend to the earth. They evoke the soul of Socrates or Confucius, as easily as that of a defunct relative, and they are so simple as to imagine that these souls come at their call to converse with them. A person who is called a _medium_ is the intermediary between the invoker and the soul invoked. The medium, under the influence of an unconscious and habitual hallucination, writes down on paper all the answers made by the spirit, or rather he writes down everything that comes into his own foolish head, imagining himself to be faithfully transmitting messages from the other world. The people who listen to him take these things, which are simply the thoughts of the ignorant medium, for revelations from beyond the tomb. In spiritualism there exists only one true and rational idea; it is the possibility of man's placing himself in relation with the souls of the dead; but the coarse means resorted to by the partisans of this mystic doctrine, cause every enlightened and educated man to repudiate any fellowship with them. We merely mention spiritualism in this place as a vulgar and foolish phase of the popular belief in ghosts. It has higher pretensions, but science and reason alike forbid us to admit them.