The Earth now has 8 billion people. This man wishes there were none.

“It was very good news for me that this kind of group existed, because usually, with this kind of philosophy, you feel alone,” said Mario Buenfil, 73, a water engineer in Mexico City involved in the movement. for 20 years. years.

Yet the words “voluntary human extinction” often elicit sputtering reactions of horror, and terms like “eco-fascist” and “Malthusian” are often hurled at the group. John Seager, the president of Population Connection, a nonprofit that advocates population stabilization through voluntary means, likened it to a sideshow. Yet if the group’s defiant name and seemingly pugilist stance suggest an embittered or even menacing founder, Mr. Knight seems anything but.

Tall and gentle, Mr. Knight comes across as lucid and thoughtful, like a mix of Bill Nye and Fred Rogers. While Mr. Knight may be against the creation of more humans, he shows great compassion for those who already exist.

A substitute high school teacher for most of his professional life, Mr. Knight is looked upon with affection by students. He spends hours every Sunday morning picking up litter from the nearby main road. During an interview, he stopped to appreciate two juicy garden spiders sunning themselves on gauze webs woven between hedges and lawn chairs. The sight was cause for celebration, Knight said, after so many creatures were killed during last year’s heat dome in the Pacific Northwest. A self-proclaimed serial monogamist, he lives alone, but his girlfriend lives next door and is fully on board with his cause.

“He doesn’t have a giant ego to strut around with, he doesn’t try to argue with people,” said Marv Ross, Mr Knight’s former roommate and longtime friend. “He was always on the humor side, to make his message as fun as possible, and I’ve seen him do that many times. He would deflect people who got upset with a joke or a smile.

Growing up in a tolerant family in Oregon, Knight watched logging companies cut down the state’s forests. After drafting into the military during the Vietnam War (he served but never deployed), he attended Oregon College of Education and joined the local chapter of Zero Population Growth, which cemented her resolution not to have children. “It was always because of the ecology, because of the damage that humans do to the environment,” he said.