“There’s this cycle of knowing and forgetting,” van der Kolk told me. “We discover trauma. And then when we see how horrifying and how inconvenient it is, we turn on the concept and peel off the messengers.” Without missing a beat, he segued from Janet to World War I and World War II, explaining how the military establishments in both Europe and the United States stigmatized shell shock and combat fatigue, for fear that they would undermine the war effort. It’s willful amnesia, he said, and he had plenty of more recent examples. Just a few years ago, he interviewed a group of foster children at a United States Senate hearing on the state of foster care. “Afterward, I’m sitting with the kids,” van der Kolk said. “And a judge walks past us on his way out, and he says to the kids: ‘You’re all doing so great! Look how terrific you all are!’ And I say, ‘Well, no, why don’t you ask them how they’re doing?’ These are kids that have suffered significant abuse and neglect. A couple of them are suicidal. They have substance-abuse problems. One of them cuts herself. But the judge didn’t want to hear about that any more than we want to hear about what really happens to soldiers when they’re off at war.”

Before enlisting in the Army, Eugene earned a bachelor’s degree in art history from the American University of Paris. Now he’s an antique art dealer. He lives in Queens with his wife and 3-year-old daughter but often goes into Manhattan to meet clients and visit galleries. I met him for coffee on the Upper East Side a couple of months after van der Kolk’s workshop. I wanted to know how he felt about the exercise now that some time had passed. Did he think it had any impact on his PTSD?

What intrigued him most, he said, is how well it worked in the moment. Whatever spell van der Kolk cast lingered into the next day, so that Eugene really saw me, a complete stranger, as the object of his guilt. “I was terrified of you,” he told me. It wasn’t until the following day, when van der Kolk had me forgive him a second time, that the spell finally broke and he was able to face me as just another workshop participant. “It reminded me of that movie ‘The Master,’ with Philip Seymour Hoffman,” he said. “When Amy Adams asks Joaquin Phoenix, ‘What color are my eyes?’ and he says, ‘Green,’ and she says, ‘Turn them blue,’ and you see them change color. It really reminded me of that.”

For a while at least, he said, he felt better. He recalled driving down the Pacific coast with his wife the day the workshop ended and noticing how weird it was not to feel stressed out. For weeks he was able to drive and use the subway with no trouble. “It felt like it sort of repaired my perception somehow,” he said. “I used to always feel paranoid — like, I’d get freaked out going to my doctor because there were all these security guards in the waiting room — and for a while that was lifted.”

But some of those effects were starting to fade. He was having headaches and memory problems again, and he was trying to figure out what triggered the relapse. He thought it had something to do with a painting he saw. He attended an Asian art fair earlier in the week, and an Arab dealer was selling some contemporary paintings; most of them were of soldiers, but one was of a woman. She looked like me, he said. He remembered staring at it and freezing up. The next day at a client’s house, he misplaced his briefcase. “It was like I threw it out the window,” he said. He spent 20 frantic and embarrassing minutes searching the house in a sweaty panic before he finally found it, right where he’d left it, near a window by the door.

Still, he was feeling hopeful. Van der Kolk had suggested some other possible approaches at the end of the workshop. He was planning to try E.M.D.R. next.

I asked him how he felt sitting across from me now. He said that he had to go to the bathroom and that his face felt numb around one eye. Ever since the exercise, the area around his right eye — the one he’d squinted at me with — went numb whenever he got nervous. He said he didn’t know why exactly, but he was sure it had something to do with the exercise itself. “I’ve been reading everything I can get my hands on,” he said. “It definitely helped, more than anything else I’ve tried so far. But I still have no idea what he did to me.”