Iroha is an older Japanese poem with deep connections to Japanese culture and religion. There are a number of different versions – the original cannot be read by the vast majority of modern Japanese readers. It has been translated in a number of languages but the translations lose much of the nuance and meaning.

“Although its scent still lingers on
  the form of a flower has scattered away
For whom will the glory
  of this world remain unchanged?
Arriving today at the yonder side
  of the deep mountains of evanescent existence
We shall never allow ourselves to drift away
  intoxicated, in the world of shallow dreams.” 

Abe, Ryuichi (1999). The Weaving of Mantra: Kûkai and the Construction of Esoteric Buddhist Discourse. Columbia University Press. ISBN 0-231-11286-6.

In this real-life example there are certainly lots of provisional knowledge. Our understanding of the poem has changed dramatically in the last few decades. In addition, publications of different translations have led to changes in understanding of the poem. One could argue though, that the core Buddhist / Japanese ideas in the text are not affected by the more superficial provisional knowledge.