Why can't Edward read Bella's mind?
In Chapter 9, "Theory", Edward explains this phenomenon: "maybe your mind doesn't work the same way the rest of theirs do. Like your thoughts are on the AM frequency and I'm only getting FM" (page 181). It is speculated that Bella's mind works differently from other people's and she doesn't send out the same brainwaves or whatever it is that Edward usually picks up on. Later on in the books, it becomes apparent that Bella has a gift of being able to shut others out of her mind and protect others as well. She is a shield of sorts whose mind is not touchable by those with certain powers (like vampires who can read minds or do various forms of mind control or state-of-mind altering).
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