The common or popular theory, however, is in Wales the poetico-religious one. This is, in a word, the belief that the Tylwyth Teg are the souls of dead mortals not bad enough for hell nor good enough for heaven. They are doomed to live on earth, to dwell in secret places, until the resurrection day, when they will be admitted into paradise. Meantime they must be either incessantly toiling or incessantly playing, but their toil is fruitless and their pleasure unsatisfying. A variation of this general belief holds these souls to be the souls of the ancient Druids, a fancy which is specially impressive, as indicating the duration of their penance, and reminds us of the Wandering Jew myth. It is confined mainly to the Coblynau, or dwellers in mines and caves. Another variation considers the fairies bad spirits of still remoter origin--the same in fact who were thrown over the battlements of heaven along with Satan, but did not fall into hell--landed on the earth instead, where they are permitted to tarry till doomsday as above. A detail of this theory is in explanation of the rare appearance of fairies nowadays; they are refraining from mischief in view of the near approach of the judgment, with the hope of thus conciliating heaven.