Such of these tales as were considered sacred or accounted for the origin of the people, were held in such high regard as to lay an obligation upon the tribe to see to it that a number of individuals learned and retained these texts, perhaps never in fixed wording, except for songs, but as to essential details of plot. Many collectors have recorded several versions of certain tales, thus giving an idea of the range of individual variation, and the writer herself has encountered as many as three variants for some of her stories, coming always from the narrators of different villages. But Wissler,[13] while allowing for these variations, says: "All this suggests instability in primitive mythology. Yet from American data, noting such myths as are found among the successive tribes of larger areas, it appears that detailed plots of myths may be remarkably stable." [Footnote 13: Wissler, Clark, Op. cit., p. 254.] =Intrusion of Contemporary Material= However there is another point discussed by Wissler which troubled the writer greatly as a beginner, and that was the intrusion of new material with old, for instance, finding an old Hopi story of how different languages came to exist in the world and providing a language for the _Mamona_, meaning the Mormons, who lived among the Hopi some years ago. The writer was inclined to throw out the story, regarding the whole thing as a modern concoction, but Wissler[14] warns us that: "From a chronological point of view we may expect survival material in a tribal mythology along with much that is relatively recent in origin. It is, however, difficult to be sure of what is ancient and what recent, because only the plot is preserved; rarely do we find mention of objects and environments different from those of the immediate present." [Footnote 14: Wissler, Clark, Op. cit, p. 255.] A tale, to be generally understood, must often be given a contemporary setting, and this the narrator instinctively knows, therefore the introduction of modern material with that of undoubted age. Stability, then, lies in the plot rather than in the culture setting; the former may be ancient, while the latter sometimes reflects contemporary life. Boaz[15] argues that much may be learned of contemporary tribal culture by a study of the mythology of a given people, since so much of the setting of the ancient tale reflects the tribal life of the time of the recording. He has made a test of the idea in his study of the Tsimshian Indians. From this collection of 104 tales he concludes that: "In the tales of a people those incidents of the everyday life that are of importance to them will appear either incidentally or as the basis of a plot. Most of the reference to the mode of life of the people will be an accurate reflection of their habits. The development of the plot of the story, further-more, will on the whole exhibit clearly what is considered right and what wrong."