David Limbaugh quotes an interview with Nancy in which she explains

"the modernist definition of knowledge, which says that things like religion, morality, and ethics are not a matter of genuine truth (as they were traditionally thought to be), but instead are merely personal 'values.' This is often called the fact/value split.......

The assumption is that reliable knowledge comes only from the realm of scientific "facts," which are objective, rational, and value-free. Then there's realm of "values," which may be personally meaningful, may be part of our cultural tradition--but have no intellectual content. That is, they do not give us knowledge or information about the world as it really is. In mainstream culture today, the term "values" has been redefined to mean literally whatever I value, my personal preferences......

Thus the late Christopher Reeve, talking about embryonic stem cells, said: "When matters of public policy are debated, no religions should have a seat at the table." Notice he was not weighing whether particular religious viewpoints are right or wrong; he was saying they don't belong at the table in the first place.....

Secularists used to argue that religion is false--and one could at least engage them in discussions about what is true and false. But today secularists are more likely to argue that religion does not have the status of a truth claim at all. It doesn't even belong at the table.

Among scientists, there's a story of a famous physicist who once told a colleague, your theory is so bad, it's not even wrong. It's not even in the ballpark of possible answers. That's how religious claims are treated today. They are not even in the category of things that can be rationally discussed.

......Pinker expresses a worldview that could be called scientific naturalism--i.e., nature is all that exists; there is nothing transcendent to nature, like spirit or soul or mind. He argues that our minds are nothing more than computers--complex data-processing machines.

At the same time, Pinker recognizes that morality depends on the idea that we are more than machines--that we are capable of making undetermined, free choices. So here's his dilemma: When working in the lab, he adopts what he calls "the mechanistic stance," treating humans as complex mechanisms. But then, he writes: "When those discussions wind down for the day, we go back to talking about each other as free and dignified human beings."

In other words, when he goes home to his family and friends, his
scientific naturalism doesn't work. You can't treat your wife like a
complex data processing machine. You can't treat your kids like
computers. So in real life, Pinker admits that he has to switch to a
completely contradictory paradigm. Here's how he puts it: "A human being is simultaneously a machine and a sentient free agent, depending on the purposes of the discussion.

Francis Schaeffer used a graphic image to describe what's happening here:

He said people are making a secular leap of faith. Intellectually they embrace scientific naturalism. That's their professional ideology. But it doesn't fit their real-life experience. So what do they do? They take a leap of faith to the upper story where they affirm a completely contradictory set of ideas like moral freedom and human dignity--even though these things have NO BASIS within their own intellectual system......

Marvin Minsky at MIT is famous for his punchy phrase that the human mind is nothing but "a three-pound computer made of meat." But he takes a secular leap of faith as well. In The Society of Mind he writes: "The physical world provides no room for freedom of will." Yet "that concept is essential to our models of the mental realm. [And so] We are virtually forced to maintain that belief, even though we know it's false."

This is an astonishing statement. Because of their experience of their own human nature, people are forced to affirm certain things--like moral freedom--even when they "know" these ideas are false, based on their naturalistic philosophy.

This is the tragedy of the postmodern age. The things that matter most in life, the things that make us truly human--like freedom and dignity, meaning and significance--have been reduced to nothing but useful fictions. Necessary illusions. Convenient falsehoods.

Of course, the very fact that these thinkers have to make a leap of faith ought to tell them something. It means that scientific naturalism is not an adequate worldview. After all, the purpose of a worldview is to explain the world. And if it fails to explain some part of the world, then there's something wrong with that worldview.....

Why aren't religious conservatives out there making this case? Why have they been so slow to recognize the impact of the divided concept of truth? The answer is that it has seeped into their own thinking as well. They often call it the sacred/secular split. To give just one example, I recently read an article by a young writer who had just graduated from a Christian high school. On the first day of class, she said, my theology teacher drew a heart on one side of the blackboard and a brain on the other side. He told us that the two are as divided as the two sides of the blackboard--the "heart is what we use for religion and the brain is what we use for science."

Obviously, religious people have to start by cleaning their own house. To gain a public voice, they will have to recover a unified view of truth that asserts the objectivity of religious truth claims. They need to be willing to stake out a cognitive territory, and then be prepared to defend it......

We have to directly address the divided concept of truth that functions as a gatekeeper to keep certain ideas out of the public debate altogether. We have to recover a sense that truth is a unity--that the universe is a single intelligible structure that includes both a physical order and a moral/spiritual order. On that basis, knowledge can once again become a unified whole, big enough to explain all of reality, all of human experience. As I put it in my book, we have recover the concept of Total Truth.

Update
This comes from a lecture transcript available online in a nicely formatted PDF document