Indoctrination is successful when you can no longer tell your memories apart from your recollection of stories.
You have people, especially those who have studied history in school, confuse stories they were taught in school with events they actually remember.
For example, someone might want to make a point about their political philosophy and say something like, "If you remember, Mandela refused to leave prison until segregation had ended." And most of the time, if they are talking to you, you'll just instinctively nod as if you remember.
No, bitch. You don't remember shit. None of that shit happened. These are stories that people package for their own benefit. There is no day when Mandela said, "I will stay in prison unless there is no apartheid."
Even if these stories are based on real events, there are so many events compressed into a narrative in a story that if you let someone trick you into recalling a narrative from a story as if you're recalling an event that actually happened, you're fully indoctrinated.
The only things you remember are the things that have had contact with your five senses: the smells, the touch, the tastes, the sights, the sounds. Everything else is a narrative. You should be able to remember the symbols, but if you don't pay the right attention, those symbols will trick you into remembering things that did not happen.
And that is the base of all propaganda. All art is propaganda. Including your favorite story.