The Big Lie, and why it works

We must not underestimate the ability of humans to lie to themselves to protect their world view.
Look at the simple, obvious case of the concept of race as a definer of humanity not pigmentation. Centuries ago, the Pope declared that Africans were descendants of Cain (if I remember that myth correctly) and therefore weren’t real people*, so it was OK to keep them as slaves. This transformed the long standing practice of slavery from “those were the unlucky people who lost the war, or who were captured” to “those aren’t people” (even though they clearly are). That this is clearly self deception is shown in all the examples of people who know that the ones THEY know are different, but the others aren’t. They loved the mammy who raised them, but were willing to set that awareness aside when it came to an overall perception.
Once someone is taught a way of thinking (or even doing things), to change it becomes incredibly painful. Doctors will cling to old practices long after they have been proven ineffective or dangerous- because they can’t admit to themselves that they are hurting their patients. Parents will convince themselves that their children are not being hurt by the school system, or abusers, because that would require them to feel responsible for allowing it. The lie can often be so much easier it’s almost impossible to resist. It’s self protection.

* this does beg the question: If that is true, why did they insist on Christianizing their slaves? Did they preach to their farm animals?