I was asked about this earlier this week...
(Adapted in part from Scott Klusendorf’s book The Case for Life, Crossway, 2009. For a more complete analysis of this shift, see R. Scott Smith, Truth and the New Kind of Christian (Wheaton: Crossway Books, 2006) pp. 23-33; see also Smith’s lecture notes “Ethics and the Search for Moral Knowledge,” Biola University, March 2004. I owe much of my insights here to Smith’s work.)Western culture has undergone a dramatic shift from moral realism (the conviction that objective morals exist even if I don’t recognize or acknowledge them) to moral non-realism (the belief that morals are merely subjective opinions). The following sketch of moral knowledge from the ancients until now, though by no means complete, highlights this shift.
We begin our history with the moral realism of the Old Testament, where moral truth is both real (objective) and knowable. From Moses forward, biblical texts point to objective moral truths that exist independent of my thinking they exist. That is, my believing them to be real does not make them real. Instead, moral truths are grounded in the character of God and accessible to all His people. (See Deut. 30: 11—“For this commandment that I command you today is not too hard for you, neither is it far off.”) At times, these objective moral standards take on a utilitarian application, as in Deuteronomy. 30: 19--“Choose life, that you and your family may live.” However, this utilitarian application does not cheapen the objective truth standards, but instead shows their practical benefits.
Even secular thinkers like Plato and Aristotle recognized these objective moral truths. For Plato, universal morals are grounded in the world of ideas (forms) but are nonetheless real. For Aristotle, objective morals are rooted in the nature of man, namely, his immaterial soul or essence. Moreover, man can know what’s right and wrong through the rational faculties of the soul. Man’s duty, then, is to cultivate virtuous habits so that he acts and behaves in a manner consistent with (and proper for) his nature as a human being. Both man’s nature and the standards he is obliged to obey exist objectively.
Moral realism continues with the New Testament writers, but with one significant addition. Not only is moral truth real and knowable, it is also transforming. That is, while ethics are deontological in their foundation, they do not end with “duty for duty’s sake.” Rather, through the transforming power of the Holy Spirit, God’s objective truth radically changes the Christian disciple more and more into the image of his Master. However, even the non-believer can know certain objective moral truths and act upon them without the aid of special revelation. The moral law, rooted in God’s general revelation, is something all men know intuitively. True, that intuitive knowledge is not sufficient to save non-believing men from their sins, but it doesn’t follow from this that they can’t recognize right and wrong—even if they work overtime to suppress that recognition. (See Romans 1: 18-32.)
During the Middle Ages, Thomas Aquinas combined Aristotle’s ethics with Christian theology, preserving the moral realism of the Biblical writers. However, there’s a slight twist. While the Biblical writers grounded objective morals in the character of God, Aquinas grounds it more or less in man’s unique nature as a rational being, a substance made in God’s image with both a body and a soul. Unlike the Protestant Reformers who come later, Aquinas is confident that human reason, unaided by special revelation, can know moral truth (an idea known as natural law).
Then comes the decisive empirical (modern) shift of the 17th and 18th centuries. For empiricists like Thomas Hobbes (1588-1679) and David Hume (1711-76), all true knowledge is restricted to what we can observe through the five senses. Since morals are immaterial things that cannot be observed empirically (i.e., we cannot taste, smell, feel, or see them), they are not items of true knowledge. Instead, they are passions and feelings, mere preferences if you will. Human nature is also diminished. Hobbes, for example, disputes that man possesses a unique immaterial nature (soul) that bears God’s image. Instead, human beings are just heaps of physical parts. Morals are reduced to self-interest and only a dominant ruler (a “Leviathan”) can keep self-interested humans from tearing each other apart.
Immanuel Kant (1724-1804) attempts to rescue objective moral truth from empiricism, but his solution is problematic. For Kant, we cannot know things as they truly are (the noumena), only as we perceive them through our senses (the phenomena). We are trapped behind our sense perceptions. However—and here Kant takes a bizarre leap—we must act as if an objective moral law-giver exists (i.e., God) and trust our transcendent minds (or universal ego) to get at the truth. While morals themselves may not be objectively knowable, at least our transcendent minds are universally so. Problem is, does Kant really know this or is he trapped behind his own sense perceptions?
The influence of Hobbes, Hume, and Kant is still felt today. If morals are not real and knowable, who are you to push your views on me or anyone else? Morality is reduced to mere preference, like opting for chocolate ice cream over vanilla.
For the most part, Christians in the 18th and 19th centuries did not respond to these empiricist attacks with anything like a vigorous intellectual counterpunch. At first, they simply surrendered. The father of Protestant liberalism, Friedrich Schleiermacher (1768-1834), proposed a strict dichotomy between faith and what’s really true. The historical reliability of the Christian faith, along with its doctrines, could be set aside. What mattered was individual religious experience. Thus, even if the resurrection and other doctrines were disproved scientifically, faith could survive as feeling.
Later, those believers who resisted liberalism grew suspicious of intellectual ideas altogether, retreating first into revivalism—where emotional, simplistic preaching produced converts with no real grasp of Christian ideas—and then into fundamentalism, where Evangelicals committed to Biblical truth withdrew from the universities to form their own Bible colleges and seminaries. While evangelical fidelity to theological orthodoxy was truly commendable, the retreat from the marketplace of ideas further marginalized Christians.
Finally, we arrive at the post-modern turn of the 20th century and its leading analytical philosopher, Ludwig Wittgenstein (1889-1951). The preceding modern view (Kant) said that we were trapped behind our sense perceptions and therefore can’t get at the truth. For Wittgenstein, truth can't be known because we are trapped behind language. Sure, we can talk about truth all day long, but there is no correspondence between what we say is real and what actually is real. We must therefore construct morals and religion through our various language communities, just as we do law.
Postmodern thinking had a near-catastrophic impact on religion and ethics. If there is no truth in religion, why should anyone take seriously a worldview that’s just a construct of the Christian language community (or any other community)? If the postmodern view is correct, it follows the Gospel can make no real truth claims whatsoever on a Muslim or Hindu who comes from a different faith (or language) community. Privately, gospel teaching may enhance the Christian’s personal life, but we should never think of it as genuine knowledge.
Ironically, that hasn’t stopped Christian postmodernists from making sweeping (universal) knowledge claims of their own. According to Brad Kallenberg, we are indeed trapped behind language and can’t get out to the real world. Thus, language does not represent reality; it constitutes reality. Question is, how can Kallengberg know this given his claim that no one has privileged access to what is real? Is it true that we are trapped behind language or is that just the view of his community? If it’s just the view of his particular language community, why should I accept it? Attempts to ground the truth of Christianity in postmodernism are bound to fail. Again, why should anyone take the Christian worldview seriously if it’s just a construct of our own language?
Meanwhile, the postmodern turn fractured the concept of moral truth in countless ways. We’re now told the Christian language community socially constructs Christian morality while Islamic and Jewish communities socially construct their respective moral rules (and so on and so on). What’s true according to one community’s article of faith may not be true for anyone else. Hence, one community should not impose its moral views on another.
Christians cannot accept this postmodern turn. Simply put, credo matters more than experience. The Corinthians had all kinds of religious experiences, yet Paul says that absent the gospel he preached, their faith was in vain. Put simply, Christianity has to mean something specific or it ceases to be Christian, no matter what one may feel. At a minimum, it means four things. First, Christ atoned for our sins. Second, he was buried bodily. Third, he was resurrected bodily. Fourth, we can know it really happened—there were witnesses. Deny any one of these and you no longer have Christianity, no matter how “authentic” you feel. Yet deny is precisely what some “Christian” authors do when they insist we can’t know anything objectively, including theological truth, because we are trapped behind language. Setting aside the self-refuting nature of their claim—namely, is their own view true or just a construct of their language community?—the Bible presents a radically different picture.
I like how one of my Biola professors, Dr. R. Scott Smith, once put it when he said that God has indeed spoken, as a fact of reality, and that he is making a universally true claim. That claim is that all should repent, and that Jesus will judge them. And, most significantly, He actually has raised Jesus from the dead. For Paul, these are facts about the way things really are, and they are true for all people. In short, Christian postmodernism nullifies the gospel.