The former archbishop of Canterbury, Rowan Williams, said Thursday that climate change is humanity’s “largest challenge ever” while warning that some climate change skeptics are driven by “sinister” conspiracy theories.

Some people are reluctant to acknowledge the climate emergency because it would require them to change their behavior, Williams told Grayson Perry in an interview on BBC Radio.

“For some people, it is just too uncomfortable to face,” Williams said. “This will require me to stop doing a lot of things I like doing. It will require our society, our civilization to think again about the levels it expects of comfort and security.”

“For others, I think there’s a rather a more sinister feeling that this must be some kind of conspiracy,” the archbishop said. They assume that “climate change has been invented by communists, illuminati, or some mysterious group who are determined to undermine who we are.”

“So that’s something I worry about a bit more,” he said, “the idea that there are people who genuinely believe climate change is a huge confidence trick.”

Introduced as “an expert on the nature of belief,” Williams, senior prelate for the Church of England from 2002 and 2012, expressed his own unshakable belief in the climate crisis, insisting that it is “everybody’s problem.”

“At the moment we’ve got arguably the largest challenge ever to the human race in the shape of an environmental crisis,” Williams said.

“We are vulnerable as a human race and it’s not about a problem coming from outside; it’s everybody’s problem, everybody’s issue,” he said.

“It’s not about something that legislation alone can cure,” he stated. “Somehow, we have to get a good story about ourselves in relation to the environment, we’ve got to have some myths and metaphors about how we relate to harmonious, non-violent, non-destructive way to the whole of this balance, this ecology that we’re part of.”

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