I’ve read Bill McKibben’s work. I’ve admired Bill McKibben’s work. Hell, I’ve even been lucky enough to edit Bill McKibben’s work. But not until Friday did I meet the man in person.

A featured speaker at Greenbuild, McKibben — tall, slight, and soft-spoken — held a crowd of hundreds in thrall as he outlined the climate challenges ahead, his 350.org movement, and the steps people could take. Afterwards, I listened as audience members approached him. A real-estate exec from St. Louis who wanted to know how he could help. An entrepreneur working on corporate sustainability who wanted help. A Montana woman who had organized her area’s Step It Up rally. A businessman from India who told McKibben he was “an inspiration to us.” More than one young, fawning female — one of whom said he was the entire reason she’d come to the conference, he was her personal hero, and that “your book Deep Economy changed the entire trajectory of my life.”

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And I don’t know how he did it, but McKibz (as I fondly and unprofessionally call him to myself) responded to each one with earnest believability. To the Montana Step It Upper: “I saw those pictures! I remember!” To the hero worshipper: “Thanks for coming. That made my day.” To a woman who asked him to speak at her organization: “I’d love to. The only problem is my complete lack of time.”

He gave the crowd a great deal of that precious time, before leaving to deliver another speech an hour south. To think that a nerd (and I mean that with all due respect and affection) could hold such sway over people gives me satisfaction. To think that he is working to change our world gives me great hope.

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