With the same propitiatory ends in view as modern Celts now have in offering food to fairies, ancient peoples, e. g. the Greeks and Romans, maintained a state ritual of sacrifices to the gods, genii, daemons, and to the dead. And such sacrifices, so essential a part of most ancient religions, were based on the belief, as stated by Porphyry in his _Treatise Concerning Abstinence_, that all the various orders of gods, genii or daemons, enjoy as nourishment the odour of burnt offerings. And like the Fairy-Folk, the daemons of the air live not on the gross substance of food, but on its finer invisible essences, conveyed to them most easily on the altar-fire.[217] Socrates, Plato, Xenophon, and other leading Greeks, as well as the Romans of a like metaphysical school, unite in declaring the fundamental importance to the welfare of the State of regular sacrifices to the gods and to the daemons who control all natural phenomena, since they caused, if not neglected, abundant harvests and national prosperity. For unto the gods is due by right a part of all things which they give to man for his happiness. The relation which the worship of ancestors held to that of the gods above, who are the Olympian Gods, the great Gods, and to the Gods below, who are the Gods of the Dead, and also to the daemons, and heroes or divine ancestors, is thus set forth by Plato in his _Laws_:--'In the first place, we affirm that next after the Olympian Gods, and the Gods of the State, honour should be given to the Gods below.... Next to these Gods, a wise man will do service to the daemons or spirits, and then to the heroes, and after them will follow the sacred places of private and ancestral Gods, having their ritual according to law. Next comes the honour of living parents.'[218] It is evident from this direct testimony that the same sort of philosophy underlies food-sacrifice among the Celts and other peoples as we discovered underlying human-sacrifice, in our study of the Changeling Belief; and that the Tuatha De Danann in their true mythological nature, and fairies, their modern counterpart, correspond in all essentials to Greek and Roman gods, genii, and daemons, and are often confused with the dead. THE CELTIC LEGEND OF THE DEAD The animistic character of the Celtic Legend of the Dead is apparent; and the striking likenesses constantly appearing in our evidence between the ordinary apparitional fairies and the ghosts of the dead show that there is often no essential and sometimes no distinguishable difference between these two orders of beings, nor between the world of the dead and fairyland. We reserve for our chapter on _Science and Fairies_ the scientific consideration of the psychology of this relationship, and of the probability that fairies as souls of the dead and as ghosts of the dead actually exist and influence the living. GENERAL CONCLUSION