Though he described Britain as a "post-religious world," his book was inspired by the phenomenon of young people being drawn to religious groups led by charismatic leaders.
Preston stressed the need for people to understand the diversity of agnostic beliefs, and warned against conflating agnosticism with atheism. "Agnosticism just like any other label is a continuum, it's not a fixed point. I think you can have all shades of agnosticism," he said.
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