Terry Gross

In a new book about the constitutional separation of church and state, Pulitzer Prize-winning historian Garry Wills insists that that separation was meant as "the great protector of religion, not its enemy." That, as Wills tells guest host Dave Davies, hasn't stopped fervent believers from challenging the concept.

Wills, a translator of St. Augustine and author of What Jesus Meant, is an emeritus professor of history at Northwestern University; the new book is titled Head and Heart: American Christianities.

In The Secret History of the War on Cancer, environmental-health expert Devra Davis warns that we're ignoring dozens of cancer-causing chemicals, like asbestos, benzene, vinyl chloride, and dioxin.

She writes that, like the tobacco companies, the chemical industry has managed to obfuscate the carcinogenic dangers of chemical and other toxic waste.

Davis directs the Center for Environmental Oncology at the University of Pittsburgh Cancer Institute and teaches epidemiology in the university's public-health graduate program.

Snacking on water beetles in Laos, dining on dog in Korea: Tom Parker Bowles, food writer for Britain's The Mail on Sunday, Night and Day, and Tatler (and son of Prince Charles' wife, Camilla Parker Bowles), has written what he's described as "a travel book about weird food."

It's called The Year of Eating Dangerously: A Global Adventure in Search of Culinary Extremes.