“I see. The residual soul animates the brain stem; that is what you mean.”

“Yes. When you rise out of your body, you will leave a residual soul there. And when you come into this body, you will find the residual soul there as well. It’s the very same residual soul I found when I took possession. And that soul will lock with any higher soul eagerly and automatically; it wants to embrace that higher soul. Without it, it feels incomplete.”

“And when death occurs both souls leave?”

“Precisely. Both souls go together, the residual soul and the larger soul, in a violent evacuation, and then the body is a mere lifeless shell and begins its decay.” He waited, observing me with the same seemingly sincere patience, and then he said: “Believe me, the force of actual death is much stronger. There’s no danger at all in what we propose to do.”

“But if this little residual soul is so damned receptive, why can’t I, with all my power, jolt some little mortal soul right out of its skin, and move in?”

“Because the larger soul would try to reclaim its body, Monsieur de Lioncourt, even if there were no understanding of the process, it would try again and again. Souls do not want to be without a body. And even though the residual soul welcomes the invader, something in it always recognizes the particular soul of which it was once a part. It will choose that soul if there is a battle. And even a bewildered soul can make a powerful attempt to reclaim its mortal frame.”

I said nothing, but much as I suspected him, indeed reminded myself to be on guard, I found a continuity in all he said.

“Possession is always a bloody struggle,” he reiterated. “Look what happens with evil spirits, ghosts, that sort of thing. They’re always driven out eventually, even if the victor never knows what took place. When the priest comes with his incense and his holy-water mumbo jumbo, he is calling on that residual soul to oust the intruder and draw the old soul back in.”

“But with the cooperative switch, both souls have new bodies.”

“Precisely. Believe me, if you think you can hop into a human body without my assistance, well, give it a try, and you’ll see what I mean. You’ll never really experience the five senses of a mortal as long as the battle’s raging inside.”

His manner became even more careful, confidential. “Look at this body again, Monsieur de Lioncourt,” he said with beguiling softness. “It can be yours, absolutely and truly yours.” His pause seemed as precise suddenly as his words. “It was a year ago you first saw it in Venice. It’s been host to an intruder without interruption for all of that time. It will play host to you.”

“Where did you get it?”

“Stole it, I told you,” he said. “The former owner is dead.”

“You have to be more specific.”

“Oh, must I, really? I do so hate to incriminate myself.”