Jews have a special relationship to books and the Haggadah has been translated more widely and reprinted more often than any other Jewish book. It is not a work of history or philosophy not a prayer book user's manual timeline poem or palimpsest - and yet it is all these things.
If no other knowledge deserves to be called useful but that which helps to enlarge our possessions or to raise our station in society then Mythology has no claim to the appellation.