A joke I made with a friend about Voldemort being a Sith Lord started me wondering about this.
In Star Wars, a person's sensitivity to the Force changes depending on their midichlorian count. And then I remembered reading that some squibs in Harry Potter can cast some simple spells.
Are there different levels of sensitivity to magic in the magical world of Harry Potter? I don't mean talent, I mean a different level of sensitivity to magic, which could lead to one person doing things another can't due to the innate sensitivity. And if there are different levels of sensitivity, is there any idea what causes that?