This book does not pretend to be a convincing, but merely an illustrative collection of evidence.  It may, or may not, suggest to some readers the desirableness of further inquiry; the author certainly does not hope to do more, if as much.

It may be urged that many of the stories here narrated come from remote times, and, as the testimony for these cannot be rigidly studied, that the old unauthenticated stories clash with the analogous tales current on better authority in our own day.  But these ancient legends are given, not as evidence, but for three reasons:  first, because of their merit as mere stories; next, because several of them are now perhaps for the first time offered with a critical discussion of their historical sources; lastly, because the old legends seem to show how the fancy of periods less critical than ours dealt with such facts as are now reported in a dull undramatic manner.  Thus (1) the Icelandic ghost stories have peculiar literary merit as simple dramatic narratives. (2) Every one has heard of the Wesley ghost, Sir George Villiers’s spectre, Lord Lyttelton’s ghost, the Beresford ghost, Mr. Williams’s dream of Mr. Perceval’s murder, and so forth.  But the original sources have not, as a rule, been examined in the ordinary spirit of calm historical criticism, by aid of a comparison of the earliest versions in print or manuscript. (3) Even ghost stories, as a rule, have some basis of fact, whether fact of hallucination, or illusion, or imposture.  They are, at lowest, “human documents”.  Now, granting such facts (of imposture, hallucination, or what you will), as our dull, modern narratives contain, we can regard these facts, or things like these, as the nuclei which our less critical ancestors elaborated into their extraordinary romances.  In this way the belief in demoniacal possession (distinguished, as such, from madness and epilepsy) has its nucleus, some contend, in the phenomena of alternating personalities in certain patients.  Their characters, ideas, habits, and even voices change, and the most obvious solution of the problem, in the past, was to suppose that a new alien personality—­a “devil”—­had entered into the sufferer.

Again, the phenomena occurring in “haunted houses” (whether caused, or not, by imposture or hallucination, or both) were easily magnified into such legends as that of Grettir and Glam, and into the monstrosities of the witch trials.  Once more the simple hallucination of a dead person’s appearance in his house demanded an explanation.  This was easily given by evolving a legend that he was a spirit, escaped from purgatory or the grave, to fulfil a definite purpose.  The rarity of such purposeful ghosts in an age like ours, so rich in ghost stories, must have a cause.  That cause is, probably, a dwindling of the myth-making faculty.