Blood prejudice. [ He pauses for a moment, because, you know, different worlds thus different politics ] They've taken it to the extreme and are using it as a way to define who you are. You're only a wizard if you're pure. You born of two mug-humans, well, you're just gonna have a fine day. [ not ]

Part human? How does that even work? [ well, James, if you asked Voldemort that, he might be able to tell you ]