"Feelings are more important then truth"
Feelings are also the best way to sell something. Get someone angry or afraid and they will 'buy' anything to feel safe again. Convince them that feelings are more important then truth then you don't even have to sell anymore, they just buy it. Start when they are young and trusting, like in school, and you don't have to convince them, just keep repeating it as truth and that is how they will see it.