" 'Do you hear voices? Do you feel the need to hurt people at times? Do you feel the need to hurt yourself?' " Mr. Clarke recalled being asked. "I don't, and I never do and I never will. Never have."
The shrinks also asked him why he had climbed the side of The New York Times Building on Thursday evening, and Mr. Clarke, 32, said he wanted to bring attention to malaria. A few hours earlier, another guy climbed the same building, and said, approximately, that he did it to stop global warming.
The age of the pointless public prank has passed: No self-respecting alpha boy will show off unless he can dress up as a superhero crusading against some ailment, cosmic or human.
And he certainly won't let someone else beat him at the same stunt.
Mr. Clarke — a pleasant, bright man, 140 pounds and 5-foot-8, who works in computer support at a marketing company — presented himself this week as publicly penitent for the danger he posed to passers-by and rescuers, as well as a man overtaken by his passion to fight malaria.
It turns out that he had been studying the building for two years, picturing how he would get from the ground to the ceramic rods that seem to form a very wide ladder on each side of the building. "There was another day in mind" for the climb, he said, but on Thursday morning, he learned that a French stuntman, Alain Robert, had beaten him to it.
Mr. Robert had eaten off the plate of Mr. Clarke's imagination.
"To dream up something that's almost unthinkable, and to see it performed not by yourself, is a shock in itself," Mr. Clarke said.
At lunch hour, Mr. Clarke, who lives in Brooklyn, went directly to Paragon Sports near Union Square and bought a pair of climbing shoes for $130. Then he bought a T-shirt at the Gap, and some rubber stamps at an art supplies store. "It was just sort of a blur of decision making," Mr. Clarke said.
Back at the job, he stamped an anti-malaria message on the new T-shirt. He told two friends about his plans, and they all left at 5 o'clock.
"I got off the subway, I knew what I was doing," Mr. Clarke said.
Mr. Clarke, who went to Far Rockaway High School in Queens, said that he first climbed rocks in Central Park as a little kid. He got involved in the extreme end of sports like snowboarding and mountain biking, and said that he secretly climbed "tall structures" in New York, like the Hearst building and the Brooklyn Bridge, at night, though he would not elaborate on statements he made to the police about those climbs.
In 2006, he said, he attended a presentation about the Times Building, a skyscraper that opened in 2007. He studied a scale model and collected written materials on the design. He fortified his spirit with "The Man Who Walked Between the Towers," a children's book about Philippe Petit, the Frenchman who danced on a high wire strung between the towers of the World Trade Center in 1974.
Last Thursday, one of Mr. Clarke's friends videotaped him as he moved from the sidewalk up the base of the Times tower. Traffic stopped. Thousands watched from Eighth Avenue.
On the way up, he spotted broken rods. "I kept my eye on them so I wouldn't stand on them," he said, adding that he was conscious of how much weight he put on each one, using his arms and legs to support himself. "That was part of my calculation. If I weigh 140 pounds and one limb is on one rod, it would have to withhold 35 pounds, per limb."
When he was about five floors from the top, police officers and firefighters lowered a rope with a piece of wood attached. "They asked me to grab hold of the rope and tie it around myself," he said. "At that height I'm going to grab to a piece of rope dangling in the air? It didn't seem logical. I told them I would be right up there, just to hang tight."
Arms aching, he took his time going the last few floors to the roof, where the rescuers hauled him in. "They were really, really nice," he said. "I said: 'I'm sorry. I'm really sorry for all the commotion.' They said, 'It's O.K., don't worry, you're crazy.' "
When he was taken to be booked, he quickly fell into conversation with one of the other prisoners. "He was just sitting there, and I was escorted into the same cage," Mr. Clarke said. "I said, 'Hey, you're Alain Robert.' We were together there for 10 minutes before he was taken away.
"I did tell him why I was climbing, and I don't think he had a comment," Mr. Clarke said. "He had his own cause. His was global warming, but I prefer mine."