He can see the confusion, the revulsion -- which doesn't prickle at him personally, he knows what he is and what happened to him -- and the morbid curiosity. Cade's at a point where his system is failing him, where he isn't getting the help he needs.

And Bull hates leaving a puzzle unsolved.

"Doesn't have to be as extreme as that, though. If you want, I've got a few techniques. Might do you some good."