Well, that's true with most things. Our entire civilization is predicated upon foundational knowledge. 80% of everything you "know" is provided to us by word of mouth. To build a body of knowledge is to create a picture of what we know. In turn laying new pictures atop. For people who have been told a different version, the common picture we all "know" is shredded and destroyed. Which makes room for a new picture to be established. Opening the door for a new foundation. “Every record has been destroyed or falsified, every book rewritten, every picture has been repainted, every statue and street building has been renamed, every date has been altered. And the process is continuing day by day and minute by minute. History has stopped. Nothing exists except an endless present in which the Party is always right.” ― George Orwell, 1984