Naturalism and morality: The only thing that’s wrong is everything you know

In my post a couple weeks ago, I considered whether naturalism is as exclusively and objectively scientific as its proponents suggest. We saw that naturalists typically begin with an a priori assumption that there is no God, which, if true, would mean the naturalistic worldview is true by default. Since the nonexistence of God is an unprovable starting point rather than an empirical conclusion, the naturalist’s foundational assumption is, in a sense, unscientific. However, it would be unwise to press that point too far. If we want to challenge the naturalistic worldview, we need to offer something more compelling than “but you can’t prove God doesn’t exist.”

There are two main ways in which a Christian can respond to the challenge of naturalism. The first is to avoid the sphere of science altogether and focus on other reasons for belief in God. After all, if theism is true, naturalism must be false, across the board. To the degree that faith or experience or historical evidence or anything else give reason to believe there’s a God, naturalism is undermined. The Holy Spirit crying with our spirit “Abba Father” offers an absolute refutation of naturalism before even a shred of scientific evidence is considered.

If naturalism is false, though, we can expect it to falter even in the scientific realm. And if there’s further evidence which might sow seeds of faith in someone’s life, why not offer it? This brings us to the second possible response to naturalism, attacking it on its own ground.

Since the naturalist’s atheistic assumptions mean the naturalistic worldview must be true, any holes in the theory at present are seen merely as questions awaiting naturalistic answers. After all, as a reasonable Christian would agree, science does not and cannot be expected to immediately discover all the answers to every conceivable question. Thus, the theistic apologist cannot just point to areas where naturalism hasn’t answered all the questions yet; the scientific case against naturalism will only be compelling if it points to areas which appear, for one reason or another, intrinsically unanswerable by naturalism.

A number of interesting arguments along those lines focus on the existence or organization of the universe, suggesting that a naturalistic universe cannot explain either itself or its apparent design. While these arguments are persuasive, in this article and the next I intend to focus on a different set of difficulties with the naturalistic worldview: those posed by the human experience of morality and consciousness.

It may seem odd to speak of morality as a scientific question, but remember, naturalism means that everything is ultimately reducible to materialistic cause and effect which is, at least in theory, empirically discoverable. This includes our moral sense. The naturalist must either demonstrate that our moral intuitions are not actually real (even as illusions, because illusions too must be explained), or demonstrate that they can be traced to the same process of impersonal, mechanistic causation which produced everything else. Thus, for a naturalist, morality must be scientific–because everything is scientific. In the words of Dutch primatologist and ethologist Frans de Waal in Good Natured: The Origins of Right and Wrong in Humans and Other Animals, “We seem to be reaching a point at which science can wrest morality from the hands of philosophers.”

For the naturalist, Darwinian evolution is absolutely indispensable. It is best known as an alleged explanation for the diversity and apparent design of biological life, but it also offers the only plausible hypothesis for the origins of morality in a world without the supernatural. If the atheist is going to explain morality without a moral Lawgiver, he must demonstrate that what we consider good is also advantageous; that it offers the sort of survival benefit rewarded by evolution. If that is the case, evolution could explain morality in the same way it explains sight or feathers or opposable thumbs. At first glance, this seems impossible; there are too many good deeds which harm or even kill the doer. The soldier who jumps on a grenade to save his buddies is a hero, but he’s just lost the chance to produce offspring with those same heroic genes.

The case is somewhat stronger on a second glance, however. Those seeking a genetic explanation for morality point to the fact that good behavior typically benefits others and that, especially in a prehistoric society, those nearby were more likely to be blood relations. Thus, the hypothetical caveman who died saving his tribe from a rampaging mammoth may have experienced something less than a survival benefit for himself, but he made it more likely that his siblings and cousins, aunts and uncles, would survive and reproduce their genes–which were also, in part, his. Likewise with the tribesman who was willing to share resources with those in need, even if he suffered personally for his generosity. Similar scenarios can be offered for most other actions we would call good, which leads the naturalist to argue that the development of morality could be explained through what we might call survival of the lucky relative.

Because God’s law for human interaction is “love your neighbor,” it is ripe for this sort of argument. Some Christian apologists have tried to respond by looking for particular types of moral behavior which are hard to explain in this way, but when Jesus himself summarizes morality as “Do unto others…” it is hard to avoid the conclusion that most types of interpersonal morality are going to end up being at least somewhat plausibly explainable in evolutionary terms. This doesn’t mean they evolved; it just means they will look like they could have.

Of course, “love your neighbor” is only half of the law. “Love the Lord your God…” is harder to explain through evolutionary theory. Though attempts have been made, it’s far from clear how the universal human instinct to seek and sacrifice for a deity can be explained through any sort of survival-based mechanism. The marmot which emerges every evening to bow before the setting sun and ceremonially burn part of its stash of winter food is unlikely to enjoy a long or prosperous life. And unlike altruistic behavior, which does have some faint echoes in the animal kingdom (the sacrifice of worker bees, for example, or the cooperation of dolphins to protect the weak), no animals exhibit even a hint of behavior which could be suggested as an evolutionary precursor to human worship. It is just there, written with bold, intentional strokes on the human heart.

So the vertical moral instinct seems much harder to explain than the horizontal. But even with the latter, difficulties emerge for the naturalistic picture. Even if we stipulate for the sake of argument that an evolutionary process might have resulted in something that looked very much like human morality, the resemblance would be entirely external.

Evolution makes no moral judgments about the instincts it selects. When a male lion takes over a pride, he immediately kills all the baby lions so their mothers come back into heat. Certain species of ducks mate so coercively that ornithologists refer to the act as a “rape.” Murder and cannibalism are routine occurrences among chimpanzees. And every one of those acts is in precisely the same moral category as heroism, self-sacrifice, and love if the naturalistic explanation of ethics is correct. The lion who devours another’s cub, and the man on the Titanic who steps out of a lifeboat to make room for someone else’s child, are both exhibiting amoral, instinctive behavior.

For the Christian, the moral law consists of a set of transcendent values written on the human heart. For the naturalist, the moral law consists of a set of useful instincts written on the human genome. As Michael Shermer put it in The Science of Good and Evil, “Our moral sentiments–the moral emotions contained within our mental armor–evolved out of premoral feelings of our hominid, primate, and mammalian ancestors.”

If the Christian explanation of morality is correct, murder is wrong. If the naturalistic explanation of morality is correct, murder feels wrong because prehistoric man found it maladaptive. The evolutionary picture simply cannot be extended to include the fact that murder actually is wrong in any meaningful sense. If our moral code is the product of evolution, then it was written by blind chance and contains nothing more than a catalogue of the instincts that helped our long-dead ancestors survive. Any sense that we ought to do what it tells us is simply a genetic relic that carries about as much true moral compulsion as we can find in the existence of wisdom teeth or tonsils.

This doesn’t mean that evolutionary ethics would leave us with a hellishly amoral world. Even if our sense of right and wrong was nothing but an evolutionary artifact, it would still carry all the instinctive force that sends songbirds south and organizes ant colonies. (In fact, the real question might be why truly good people are so rare if morality works through our instincts rather than, as the Christian believes, against them.) One could even argue from a naturalistic perspective that it makes sense to follow the dictates of our moral intuition simply because it is nicer to feel good than guilty, even if we know both are nothing but meaningless synaptic flickers. But what evolutionary morality can never explain is how something could actually, objectively, truly be wrong.

Take any example you like: the brutal beatings of gay activists in Russia, the torture and massacre of innocents in Syria, the casual sexual violence against women in Egypt. If the naturalistic picture is correct, our horror and anger at these stories is nothing but an automatic, amoral response accidentally bred into the human race, and any attempt to stop violence and exploitation is nothing but selfish and irrational meddling. If, instead, we find within ourselves the knowledge that anything at all–any single thing–is really, actually wrong, then morality must be something more than mere genetic happenstance.

So yes, it’s true that evolution can piece together a picture of morality that more or less explains our moral behavior and even our moral intuitions. But the story comes with a tag attached: “Everything you think and feel about what’s right and wrong is false, and even after you say you believe this, you won’t be able to live by it.” If there’s another story which can explain that same moral experience without needing to dynamite everything we think is true, it’s worth asking if perhaps that story is the right one.


An upcoming post will consider another difficulty with naturalism: its inability to explain human consciousness.

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