“Are you surprised how much pain you’re capable of surviving? Are you wondering how your consciousness can even contain suffering of this magnitude? It’s OK to be curious. The thing to remember is, the human body today is really no different than it was twenty thousand years ago. The circuits of pleasure and pain are as they were. So you might think that there is no difference between the experience of being tortured to death during, let us say, the Spanish Inquisition and the experience that I can offer you. You might think that, wouldn’t you? But, speaking as something of an aficionado, I’d have to say you’d be wrong. Our evolving understanding of neurochemistry is really quite valuable. Ordinarily, the human body has the equivalent of a safety valve: when C-fiber stimulation reaches a certain level, endorphins kick in, blunting and assuaging the pain. Or else unconsciousness results. God, it used to piss me off when that happened. Either way, the phenomenology of pain is limited. It’s like brightness: you can experience only a certain level of brightness. You maximally stimulate the cones and rods of the retina, and after that point, there’s no change in the perception of brightness. But when it comes to pain, contemporary neuroscience changes the whole game. What’s in your IV drip is absolutely crucial to the effect, my dear Angus. You knew that, didn’t you? We’ve been administering a substance known as naltrexone. It’s an opiate antagonist—it blocks the natural painkillers in your brain, those legendary endorphins. So the ordinary limits of pain can be pushed past. Not exactly a natural high.”

Another wail of agony—almost a keening—interrupted his disquisition, but Demarest was undeterred. “Just think: because of the naltrexone drip, you can experience a level of pain that the human body was never meant to know. A level of pain that none of your ancestors would ever have known, even if they’d had the misfortune to be eaten alive by a saber-toothed tiger. And it can increase nearly without limit. The main limit, I would say, is the patience of the torturer. Do I strike you as a patient man? I can be, Angus. You’ll discover that. I can be very patient when I need to be.”

Angus Fielding, distinguished master of Trinity College, began to do something he had not done since he was eight: he broke down and sobbed.