Why do cult members commit crimes, defy societal norms and even kill themselves?

Many would answer “brainwashing” and point to bizarre rituals, charismatic Svengalis and groupthink.

But language scholar and reporter Amanda Montell writes that the answer is “not some freaky mind-bending wizardry that happens on a remote commune where everyone dons flower crowns and dances in the sun. . . . The real answer all comes down to words.”

In “Cultish: The Language of Fanaticism,” Montell dives into the weird world of cults in search of the language that drives them — and the social science that trumps the pseudoscientific notion of “brainwashing.”

Using examples including the Heaven’s Gate religious group and the mass suicide at Jonestown, Montell examines how the human brain is primed to seek out profound group experiences, and how words create identity and meaning. She talks to neuropsychologists and sociologists and digs into the enormous body of research that helps explain charisma, influence and the behavior of followers.

It’s all too easy to deride followers as foolish rubes. But Montell shows the ways in which we are all susceptible to the influence of others. Humans have evolved to be gullible, she writes, and even if we think we’re not affected by cults, we probably have been swayed by cultish language and persuasive techniques.

Engaging and fun to read, “Cultish” offers plenty of jaw-dropping details about life inside cults. But the book isn’t all voyeuristic pleasure. As Montell teases out the universality of cultish influence, she upholds the humanity of the people who do get swayed.

“One’s out-of-the-box beliefs, experiences, and allegiances are less a mark of individual foolishness and more a reflection of the fact that human beings are [to their advantage and their detriment] physiologically built to be more mystical and communal than I knew,” she writes. By the end of the book, you’ll know, too.