@curmudgeonaf ... and previous experiences and associations, etc., and then, even beyond that, memories of that experience will continue to change with further experience and association and changing biases and agenda.

Orwell, in context here, is raising the specter not just of individual interpretations and agenda, but denial of the factual at all -- not only that event X didn't happen as described, but that records of event X can be simply denied as a lie, under a totalitarian regime.

Which seems dismayingly familiar these days.