Method of Examination: Exoteric and Esoteric aspects--The X-quantity--Scientific attitudes toward the Animistic Hypothesis: Materialistic Theory; Pathological Theory; Delusion and Imposture Theory; Problems of Consciousness: Dreams; Supernormal Lapse of Time--Psychical Research and Fairies: Myers's researches--Present Position of Psychical Research--Psychical Research and Anthropology in Relation to the Fairy-Faith, according to a special contribution from Mr. Andrew Lang--Final Testing of the X-quantity--Conclusion: the Celtic Belief in Fairies and in Fairyland is scientific. CHAPTER XII THE CELTIC DOCTRINE OF RE-BIRTH AND OTHERWORLD SCIENTIFICALLY EXAMINED 492-515 The Extension of the Terms Fairy and Fairyland--The Real Man as an Invisible Force acting through a Body-Conductor-- A Psychical Organ essential for Memory--Pre-existence a Scientific Necessity--The Vitalistic View of Evolution--Old Theory of Heredity disproved--Embryology supports Re-birth Doctrine--Psycho-physical Evolution--Memory of previous Existences in Subconsciousness--Examples--Dream Psychology furnishes clearest Illustrations--No Post-existence without Pre-existence--Resurrection as Re-birth--The Circle of Life--The Mystical Corollary--Conclusion: the Celtic Doctrine of Re-birth and Otherworld is essentially scientific. INDEX 516-24 PREFACE During the years 1907-9 this study first took shape, being then based mainly on literary sources; and during the latter year it was successfully presented to the Faculty of Letters of the University of Rennes, Brittany, for the Degree of _Docteur-ès-Lettres_. Since then I have re-investigated the whole problem of the Celtic belief in Fairies, and have collected very much fresh material. Two years ago the scope of my original research was limited to the four chief Celtic countries, but now it includes all of the Celtic countries. In the present study, which has profited greatly by criticisms of the first passed by scholars in Britain and in France, the original literary point of view is combined with the broader point of view of anthropology. This study, the final and more comprehensive form of my views about the 'Fairy-Faith', would never have been possible had I not enjoyed during many months the kindly advice and constant encouragement of Mr. R. R. Marett, Reader in Social Anthropology in the University of Oxford, and Fellow of Exeter College.