"I was an outsider to wizarding culture. I learned everything I could from books, but there’s much that can only be learned through immersion. Social norms, interpersonal and political hierarchies, unspoken social rules, et cetera. That’s what purebloods have an issue with. Well, that and the desire to retain their place at the top of the power hierarchy, which is only possible if they keep mudbloods and halfbloods oppressed."