Why Scientism Can’t Explain Morality or Reality

The following is a chapter written by Dr. Keith Plummer, dean of the School of Divinity at the University. This chapter was originally written for and originally published in Before You Lose Your Faith: Deconstructing Doubt in the Church, edited by Ivan Mesa (The Gospel Coalition, 2021). This book speaks directly to an audience of identifying or formerly identifying Christians who are “deconstructing” the faith they once claimed. While it might be tempting to leave the church for answers, the book argues that church should be the best place to deal with doubts.

Every semester I require students in my Christian apologetics classes to interview a non-Christian using questions I’ve prepared. I don’t want them to start a debate with the person; I just want them to become more comfortable asking questions of people who don’t share their beliefs, to practice the skill of listening, and to better understand non-Christian thought.

This is one set of the questions: “Is there anything that could persuade you that Christianity is true? If so, what? If not, why?” My students commonly hear requests for empirical or sensory evidence. Some describe this as needing “tangible” evidence, while others speak of needing “scientific” proof for the existence of God or the possibility of miracles.

In either case, people seem to assume that only what can be scientifically confirmed is worth being called “evidence.” Maybe that’s your assumption, too, and a reason why you’re deconstructing your faith. If so, I think you’re asking the impossible of science.

Science is a wonderful means of discovering the workings of the natural world. But claiming reality is restricted only to that which we’re capable of detecting with our senses is, as philosopher Alvin Plantinga has said, like a drunk looking for his lost car keys under a streetlight because the light is better there. It’s a form of naturalism or materialism, a view that holds that the natural world is all that exists. This claim is not scientific in nature but philosophical. It’s not a scientific conclusion but an ideological pre-commitment concerning the nature of reality.

Problem of Scientism

The demand that God’s existence be subject to scientific verification fails to account for the kind of being Christianity claims he is. It’s to treat God as if he is simply a part of creation rather than the one who, according to the Bible, is responsible for not only creating all that is not himself but also maintaining its existence. As the apostle Paul proclaimed to the philosophers of Athens, he is the “Lord of heaven and earth” who “made the world and everything in it” (Acts 17:24). Because all creation owes its original and continued existence to God, we shouldn’t expect him to be detectable as if he were simply a grander piece of nature’s furniture. He qualitatively transcends what he has made; he’s not a part of it. Saying you can only believe that the God of the Bible is there if empirical science confirms it is essentially to say that you’ll only believe Christianity is true if it’s other than what it is.

Not only does the demand for scientific or empirical evidence fail to recognize the limits of science, it artificially restricts the meaning of evidence. I’m not willing to concede the absence of scientific findings consistent with and supportive of a Christian perspective. But, for the sake of argument, the biblical narrative still makes sense of existential phenomena common to humanity, such as our aspirations for justice, our belief in human rights, our appreciation of beauty, and the inevitability of making moral judgments about human behavior. These values may not be scientific, but they should still be acknowledged as evidence. They’re simply other kinds of evidence.

The belief that science is the only way of knowing what’s true or real is called “scientism.” Many, even if they’ve never heard the word, take scientism for granted as if it’s self-evident. It’s so deeply ingrained in some people’s minds that they regard anyone who would dare contest it as backward and anti-scientific. But that’s to conflate science and scientism. One can (and, as I’ll argue, should) reject scientism without disparaging science. Even aside from the evaluation of Christianity’s claims, scientism is intellectually and existentially flawed. I’d like to examine just a few problems with scientism that you might not have thought about—including one major difficulty related to whether Christianity warrants your trust.

Perhaps the greatest intellectual deficit of scientism is that it’s self-refuting. It fails to meet its own standard. Remember, according to scientism, science is the only way of knowing what’s true or real. If something hasn’t been verified by science, we’re not justified in saying we know it to be true or real. We can say we believe it, but we can’t legitimately claim to know it. The problem for scientism arises, though, when we ask: “How do I know that science is the only means of knowing what’s true or real?” If that assertion is really true, then the only acceptable answer to that question would have to be “Science says.” If we appeal to anything other than science to answer the question, we’ve denied its exclusive claim. But while the sentence makes a claim about science, it’s not a scientific claim. There’s no way to establish its truth on the basis of experimentation or sensory experience. That’s because it’s not a scientific conclusion but a philosophical commitment to a particular theory about the means to and extent of our knowledge.

But self-refutation isn’t scientism’s only problem. It also has high existential costs. For example, if it were really the case that science and sensory experience are the only means of arriving at true knowledge, then we would have to admit there are many things we assume we know that we actually can’t know. For example, even though you might not be a historian, you probably think you have some knowledge of past events (globally, nationally, and locally). Is your knowledge of any of those things based on science or empirical confirmation? No, because historical knowledge is not the result of repeated experimentation and observation. A great deal of our knowledge of the past depends on the testimony of people who lived in those times. But if scientism were true, then we’d have to give up any claim of historical knowledge, since it wouldn’t be the finding of science. Even claims to knowledge of the recent past, including ours, would have to be abandoned if science is the only means of knowing what is true or real. I have no doubt that I ate a chicken burrito bowl for lunch shortly before typing this paragraph. But my knowledge of that delicious meal doesn’t rest on science. Of course, someone could pump my stomach and verify that I did, in fact, consume what I claim; that would be a finding of science. But that in no way means my confidence concerning what I ate isn’t knowledge.

Moral Knowledge

Moral knowledge is yet another casualty of scientism. When you insist that truth is restricted to scientific verifiability, you must do away with all claims concerning knowledge of right and wrong, justice and injustice, and moral obligation. Science isn’t capable of detecting or determining the existence of such entities as objective moral values and duties, since they’re not subject to apprehension by the senses. But are you willing for that reason to deny that they are real? To be consistent with scientism, you must.

To illustrate this point, I ask students to imagine this situation: to a willing participant I attach a number of devices to monitor physical activity such as blood pressure, heart rate, perspiration, brain activity, and so on. Imagine I apply to the same individual, increasing electrical shocks through electrodes attached to various parts of his body. Throughout the experiment, an assistant monitors the devices tracking his vital signs. What will the assistant observe? No doubt, we’ll find that as the voltage increases, there will be a corresponding increase in heart, blood pressure, and perspiration rates. We would probably hear vocalizations and cries of increasing decibels as the experiment progressed.

What could we legitimately conclude from this experiment? We could conclude that increased electrical voltage applied to a living subject results in mounting pain accompanied by a variety of observable elevations in the bodily systems we have monitored. What we could not conclude, on the basis of what was observed, is that one ought not inflict such pain on another. We couldn’t rightfully say, in other words, that it’s wrong to do so. Moral obligations simply aren’t the kind of thing science can detect or quantify.

But let me ask you something. Do you know it’s wrong to unnecessarily inflict excruciating pain on another? Do you know it’s really wrong to physically or mentally abuse another person? If scientism is true, you don’t and you can’t. There’s no third way. Either abandon scientism or your claim to know moral truths; you can’t have both. If moral outrage at perceived injustice, suffering, abuse, and cruelty is to be anything more than a mere expression of personal or group preference, it must be grounded in something real, unchanging, and not of our making.

Moral Objections

Moral disillusionment and disappointment with Christianity might be reasons for thinking about abandoning the faith you once professed. So many of the objections to Christianity I hear lately are moral in nature. Maybe you’ve been seriously injured by the church or someone professing to follow Jesus. Or perhaps recent revelations about the sins and hypocrisy of highly respected Christian leaders have led you to wonder whether Christianity is true. Or perhaps as you’ve watched continuous coverage of suffering caused by COVID-19, racial strife, political polarization, and various forms of injustice and dehumanization, you’ve concluded that the God you once claimed to love probably isn’t there after all. You have some sense of the way things ought to be but are clearly not. Deep within there’s a nagging sense that life is broken. You’re making inescapable moral evaluations based on what you take as real moral standards. You have a sense of moral indignation that only makes sense if, in fact, there is true right and wrong, justice and injustice. If you’re clinging to scientism, you’re undermining your moral objections to the faith.

C.S. Lewis, the Christian apologist who spent many years of his life as an atheist, recounts the effect this realization had on him. His argument against God had for a long time been based on the apparent injustice and cruelty of the universe. But then he asked himself a question that, if you haven’t already asked it, I hope you will: “How had I got this idea of just and unjust?” He added:

A man does not call a line crooked unless he has some idea of a straight line. What was I comparing this universe with when I called it unjust? If the whole show was bad and senseless from A to Z, so to speak, why did I, who was supposed to be part of the show, find myself in such violent reaction against it?

Lewis rightly realized that if the universe was all there was all there was and riddled through with meaninglessness (because there is no “Meaner” behind it), then there wasn’t anything to account for his opposition to the way things are. He would just be another part of the meaningless whole. He then made a crucial point about the relationship between his argument against God and the necessity of an objective standard of justice:

Of course I could have given up my idea of justice by saying it was nothing but a private idea of my own. But if I did that, then my argument against God collapsed too—for the argument depended on saying that the world was really unjust, not simply that it did not happen to please my private fancies.

I really dislike lima beans. (Bear with me.) I’ve despised them since childhood, when my mother would insist I eat them in servings of mixed vegetables. I found their consistency and flavor so distasteful that I did my best to swallow them. Decades later, if my wife serves mixed vegetables with lima beans, I try to down them as fast as possible without biting into and feeling their mushiness. What if I were to propose an argument, let’s call it “the problem of lima beans,” that said a good, all-powerful God can’t exist because lima beans do, and I don’t like them? Would you find that argument at all compelling? I hope you wouldn’t. God’s existence and my dislike of lima beans are unrelated. It doesn’t follow that God can’t exist because he has permitted things I don’t prefer. It wouldn’t even follow if I found a large group of others who hate lima beans. Personal and collective tastes are still subjective. My confident assertion that lima beans are nasty gives you insight into my preferences, but it doesn’t really tell you anything about the nature of lima beans.

This is what Lewis was getting at when he said that his argument against God failed if his idea of justice is simply a “private idea of my own.” His calling life unjust would be on the same order as my saying, “Lima beans are nasty,” a mere articulation of his personal taste that didn’t actually say anything about the world outside himself. In order for his evaluation that the universe was unjust to carry any weight, there had to be an actual, absolute standard of goodness and justice by which he made his assessment. This led him to conclude:

Thus, in the very act of trying to prove that God did not exist—in other words, that the whole of reality was senseless—I found I was forced to assume that one part of reality—namely my idea of justice—was full of sense. If the whole universe has no meaning, we should never have found out that it has no meaning: just as, if there were no light in the universe and therefore no creatures with eyes, we should never have known it was dark. Dark would be without meaning.

Before you conclude there is no evidence for Christianity, consider that your moral intuition bears witness to the God of the Bible. Christianity makes sense of the inevitability of making moral judgments about others and ourselves. We can try with all our might to deny it, but we can’t escape on some level thinking that there is a moral straight line, any deviation from which is evil. I emphasized the word “any” because we tend to reserve the word “evil” for what we regard as the greatest atrocities (usually those we don’t commit ourselves). But just as any deviation from a perfectly straight line constitutes crookedness, any deviation from pure goodness is evil. And that’s a problem for each of us, for which only the Christian faith is the solution.


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