The function of the slippage was to prevent interactions which might affect history.
Knowing more about them shouldn't affect history once they finally set things right.
They don't understand the text and how it affects government or history.
They witness the battle but make the difficult decision to not become involved so as not to affect history.
But plots, he finds, are dangerous and do affect history.
Every one of them had affected history in some way, large or small.
I don't think any single man can affect history that deeply.
If their death would affect history, then they won't die.
Change affects not only history, but nature itself.
In this sense actions are realized in light of the way they affect history.