she said, shaking her head. Freckled, clasped fingers twitched in her lap. "I just don't know."

She lifted a look to the pensive priest. "What do you think, Father?''

"Compulsive behavior produced by guilt, perhaps, put together with split personality."

"Father, I've had all that garbage! Now how can you say that after all you've just seen!"

"If you've seen as many patients in psychiatric wards as I have, you can say it very easily," he assured her. "Come on, now. Possession by demons, all right: let's assume it's a fact of life,, that it happens. But your daughter doesn't say she's a demon; she insists she's the devil himself, and that's the same thing as saying you're Napoleon Bonaparte! You see?"

"Then explain all those rappings and things."

"I haven't heard them."

"Well, they heard then at Barringer, Father, so it wasn't just here in the house."

"Well, perhaps, but we'd hardly need a devil to explain them." "So explain them," she demanded.

"Psychokinesis."

"What?"

"Well, you have heard of poltergeist phenomena, haven't you?"

"Ghosts throwing dishes and things?"

Karras nodded. "It's not that uncommon, and usually happens around an emotionally disturbed adolescent. Apparently, extreme inner tension of the mind can sometimes trigger some

unknown energy that seems to move objects around at a distance. There's nothing supernatural about it. Like Regan's strength. Again, in pathology it's common. Call it mind over matter, if you will."

"I call it weird."

"Well, in any case, it happens outside of possession."

"Boy, isn't this beautiful," she said wearily. "Here I am an atheist and here you are a priest and-

--"

"The best explanation for any phenomenon," Karras overrode her, "is always the simplest one available that accommodates all the facts."

"Well, maybe I'm dumb," she retorted, "but telling me an unknown gizmo in somebody's head throws dishes at a ceiling tells me nothing at all! So what is it? Can you tell me for pete's sake what it is?"

"No, we don't under---"

"What the hell's split personality, Father? You say it; I hear it. What is it? Am I really that stupid? Will you tell me what it is in a way I can finally get it through my head?" In the redveined eyes was a plea of despairing confusion.

"Look, there's no one in the world who pretends to understand it," the priest told her gently.

"All we know is that it happens, and anything beyond the phenomenon itself is only the purest speculation. But think of it this way, if you like: the human brain contains, say, seventeen billion cells."

Chris leaned forward, frowning intently.

"Now looking at these brain cells," continued Karras, "we see that they handle approximately a hundred million messages per second; that's the number of sensations bombarding your body.

They not only integrate all of these messages, but they do it efficiently, they do it without ever stumbling or getting in each other's way. Now how could they do that, without some form of communication? Well, it seems as if they couldn't. So apparently each of these cells has a consciousness, maybe, of its own. Now imagine that the human body is a massive ocean liner, all right? and that all of your brain cells are the crew. Now one of these cells is up on the bridge.

He's the captain. But he never knows precisely what the rest of the crew below decks is doing.

All he knows is that the ship keeps running smoothly, that the job's getting done. Now the captain is you, it's your waking consciousness. And what happens in dual personality--- maybe-

-- is that one of those crew cells down below decks comes up on the bridge and takes over command. In other words, mutiny. Now--- does that help you understand it?"

She was staring in unblinking incredulity. "Father, that's so far out of sight that I think its almost easier to believe in the devil!"

"Well---"

"Look, I don't know about all these theories and stuff," she interrupted in a low, intense voice.

"But I'll tell you something, Father; you show me Regan's identical twin: same face, same voice, same smell, same everything down to the way she dots her i's, and still I'd know in a second that it wasn't really her! I'd know it! I'd know it in my gut and I'm telling you I know that thing upstairs is not my daughter! I know it! I know!"

She leaned back, drained. "Now you tell me what to do," she challenged. "Go ahead: you tell me that you know for a fact there's nothing wrong with my daughter except in her head; that you know for a fact that she doesn't need an exorcism; that you know it wouldn't do her any good. Go ahead! You tell me! You tell me what to do!"

For long, troubled seconds, the priest was still. Then he answered softly, "Well, there's little in this world that I know for a fact."

He brooded, sunk back in his chair. Then he spoke again. "Does Regan have a low-pitched, voice?" he asked. "Normally?"

"No. In fact, I'd say it's very light."

'Would you consider her precocious?"

"Not at all."

"Do you know her IQ?"

"About average."

"And her reading habits?"

"Nancy Drew and comic books, mostly."

"And her style of speech, right now: how much different would you say it is from normal?"

"Completely. She's never used half of those words."

"No, I don't mean the content of her speech; I mean the style."

"Style?"

"The way she puts words together."