Michele Bachmann and I grew up in the same evangelical world. We heard similar sermons, read similar books – most importantly the Bible – and we followed the same anointed leaders.

By the time we were in college our generation of evangelicals had been educated into a profoundly different worldview than that of the secular, anti-Christian, Satan-following Ivy League elites we had been taught to fear. We understood the world to be a spiritual battleground with forces of good pitted against forces of evil. Real angels and real demons hovered about us as we prepared to wage these wars. We sang songs like Onward, Christian Soldiers in our churches. At summer camps and vacation Bible schools we stamped our feet, and waved our arms as we sang with good Christian gusto I'm in the Lord's Army. We knew which side we were on.

Our religious literature was filled with the ideas of people like Francis Schaeffer, a fundamentalist Pennsylvania pastor who transformed himself into a guru by moving to the Swiss Alps, making himself look like Heidi's grandfather, and turning his home into a refuge for troubled pilgrims called "L'Abri". Schaeffer, the intellectual architect of the religious right in America, helped a generation of young evangelicals understand that the corrosive forces of secular humanism were eating away at the foundations of the Christian west. We were heartened that such an impressive intellectual – a fundamentalist counter to Jacob Bronowski or Carl Sagan – was on our side.

Schaeffer's 1976 bestseller, How Should We Then Live?, chronicled the decline of the Christian west, which had flourished with God's blessing for centuries, but was now in decline. With broad brushstrokes, our alpine sage showed us how the west had sold its soul for a mess of secular pottage and sham materialism. Schaeffer's million-selling manifesto was made into an impressive film series, narrated by Schaeffer. Clad in his iconic Swiss leggings, with a flowing mane of white hair and trademark goatee, Schaffer took viewers to all the great cultural spots in the west to help us understand what had gone wrong. The book and film series were widely used at evangelical colleges and universities across the country.

Michele Bachmann told the New Yorker recently that Schaeffer had a "profound influence" on her developing worldview as a young person. Millions of evangelicals would murmur "amen" to that. I read Schaeffer and watched his film series at Eastern Nazarene College in Massachusetts in 1979 as part of a capstone general education course required of all students.

Schaeffer was the most charismatic of the evangelical experts that shaped the world views of believers in the 1970s. There were many more with different specialities. We learned that evolution had no scientific support from young-Earth creationists like Henry Morris and Ken Ham. When Bachmann says that "evolution has never been proven" she is simply repeating what our generation has heard from evangelical leaders as we were growing. I enrolled at Eastern Nazarene College seeking credentials that would enable me to join the creationists in their fight against evolution.

We learned that homosexuality is a choice made by people to live in sin, under Satan's influence. The reparative therapy – "pray away the gay" – used at the clinic run by Bachmann's husband was something we all endorsed, under the influence of evangelical social scientists like James Dobson, who had a PhD in child development and thus knew what he was talking about. We grew up hearing about the "gay agenda" and how it was being used by Satan to destroy traditional morality and faith in the Bible.

Christian "historians" like Peter Marshall and David Barton helped us understand that America was a "Christian nation" and that recent travails, like the social upheaval of the 1960s that gave us drug abuse, promiscuity, and the homosexual agenda, were the result of abandoning America's religious roots.

Many evangelicals, myself included, were fortunate enough to study under Christian scholars, like my professors at Eastern Nazarene College in the 1970s or my colleagues today at Gordon College, who see through the nonsensical claims of people like James Dobson, David Barton, Francis Schaeffer, and Ken Ham – who runs the preposterous Creation Museum in Kentucky. Even as a college student I recall Schaeffer being examined rather critically and young-Earth creationism dismissed out of hand.

There are, fortunately, many evangelical scholars – National Institutes of Health (NIH) director Francis Collins and historian Mark Noll come to mind – who are quietly raising alarms about all this dangerous anti-intellectualism, warning us about populist gurus who are marketing a "Christianised" version of knowledge that, on closer examination, turns out to be neither Christian nor knowledge.

Unfortunately, millions of evangelicals – and this would include much of the political base being courted by the GOP presidential candidates as well as the candidates themselves – are trapped in an alternative "parallel culture" with its own standards of truth. The intellectual authorities mentioned above – with the exception of Schaeffer who died in 1984 – all have media empires that spread their particular version of the gospel. Millions of dollars every year support the production of books, DVDs, radio shows, school curricula, and other educational materials. Very few evangelicals grow up without hearing some trusted authority – perhaps even with a PhD – tell them that the age of the Earth is an "open question". Or that scientists are questioning evolution. Or that gays are getting spiritual help and becoming straight. Or that secular historians are taking religion out of US history.

Historian Randall Stephens and I have been interested in this alternative knowledge world for years. We grew up in it and emerged from it unscathed – as near as we can tell – but many of our evangelical students over the years have arrived at college with "truths" from this alternative knowledge world written on their hearts. Harvard University Press has just published our sympathetic insiders' analysis of the parallel culture of American evangelicalism. Titled The Anointed: Evangelical Truth in a Secular Age, we look at how evangelical knowledge structures are exploited by media savvy authorities like those mentioned above.

And, as we watch the GOP candidates enthusiastically promote discredited ideas from this alternative knowledge world, we worry.