The Knowledge Argument and Frank's Response to It

The Mary argument elicits this very strong intuition that there's something there. What happens is take the knees example. When I see my knees bent in the mirror, I've got a derived belief because I believe my knees are bent but it derives from my belief that there's an image in the mirror which is indeed of my knees. But when she leaves the room, sudden she she quies a non-derived belief that the red things are very different from the green ones. That's the idea. It's old information, but it's being repackaged in a very, very different way for her and presented her with an immediacy that it couldn't possibly have had before.