James C. Scott, Seeing Like a State page 332

It is worth emphasizing the degree to which oral cultures, as opposed to written cultures, may avoid the rigidity of orthodoxy. Because an oral culture has no textual reference point for marking deviations, traditions currently in circulation vary with the speaker, the audience, and local needs. Having no yardstick like a sacred text to measure the degree of drift from its Ur-tradition, such a culture can change greatly over time and simultaneously think of itself as remaining faithful to tradition.