The fact remains that mankind has ever hoped, and will ever hope, for a continued existence of some kind; and all the old arguments in its favor, and all the promises of the Master, still hold good. Moreover, every new development in psychic science adds strength to the arguments, and fresh proofs of his wisdom. FOOTNOTES: [Footnote 37: Book on Mediums, p. 87.] [Illustration] CHAPTER XX. PHANTASMS OF THE DEAD. Ghosts.--Scientific Investigations.--Tentative Classification of Phenomena.--Power to create Phantasms demonstrated.--Investigations of the London Society for Psychical Research.--Spirit Photography.--Projection of the "Astral Body."--Witches.--Conditions necessary.--The same in all Cases.--Spirit "Materialization."--Magicians.--Ghosts the Creations of the Subjective Entity.--Eliphas Levi's Views.--Raising the Devil.--Crystal Visions.--Propositions established.--Embodied Thoughts.--Phantasms not Spirits.--Uniform Characteristics.--A New Classification.--Conditions of Objectivity and Persistency.--Haunted Houses.--No General Intelligence manifested.--D'Assier's Statements.--A Remarkable Case.--Ghosts Intensified Telepathic Visions.--Difference in Degree, not in Kind.--Ghosts not controllable by Suggestion.--Other Salient Peculiarities.--Ghosts neither prove nor disprove Immortality.--Mental Atmosphere of Houses.--Remarkable Cases.--Classification of Telepathic Phenomena.--Conclusions. There is another class of phenomena which demands a brief notice, although it does not pertain directly to the development of the hypothesis under consideration. It is that of phantasms of the dead, or ghosts. Scientific investigations of modern times have demonstrated the fact that many of the ghost-stories which have terrified the timid in all ages of the world have a real foundation in fact; that is, it has been demonstrated that certain impalpable shapes, resembling persons deceased, do from time to time appear to the living. The world is indebted more than it can ever repay to the London Society for Psychical Research for its patient, untiring, and strictly scientific investigations of this subject. Many facts have been accumulated, but they have not yet been classified with reference to any special theory or hypothesis. It is perhaps too early to formulate any hypothesis pertaining to the subject-matter. It is certainly too early to dogmatize. The most that can safely be done is to speculate tentatively, and to suggest a line of thought and investigation for those who are devoting their time to the work. It is my purpose to do this, and this alone, in the hope that if the suggestions seem to be worthy of consideration, the subject may be pursued on the lines indicated until their fallacy is exposed or their correctness demonstrated.