AFTER I WALKED between the towers of the World Trade Center 50 years ago, people said, “There’s no next project. How can you top being a quarter-mile high in the sky?” But it’s not true! I prepared for one year to do that walk, and when it was done—I mean, after the police who arrested me for trespassing let me go—I went on to the next walk and the next: the Louisiana Superdome, the Eiffel Tower, a section of Niagara Falls and many others. I am not limited by what I have done. I’m motivated by what I have done.