Since Evolution Is Blind, Isn’t Atheist Morality Arbitrary?

Since evolution is blind, isn’t atheist morality arbitrary?

In the last week, two Christians have made that claim in conversations with me: one a highly educated and intelligent engineer who was attending a meeting of a philosophy club; the other a pastor who, as such, probably has at least one post-graduate degree.

I’ll let the pastor speak for both, since I happen to have his thoughts in writing:

On the atheist rubric, integrity is an accidental byproduct of a blind evolutionary process…. There isn’t really a moral anchor for atheism, only an arbitrary preference, subject to every breeze.

Let me begin by saying that I completely understand and even empathize with the pastor’s position. It is exactly the position I maintained for four decades as an evangelical. To me, it was only the grace of God that kept the unbelieving world from descending into moral anarchy.

Imagine my surprise when, after leaving my faith, I discovered that I still wanted to do the right thing! Granted, there was some inertia from my years in the church, but I also discovered an unexpected moral core in myself.

How did this come to be?

I hope to show how evolution can produce a moral sense that is far from arbitrary and, in fact, the “arbitrary” label sticks much more readily to biblical morality than to the core morality that is our evolutionary heritage.

There are just two concepts behind evolution: descent with modification, and natural selection.Those who believe evolution is a “blind” or “chance” process understand descent with modification, but have forgotten about natural selection. Descent with modification is indeed blind. That’s where random mutations happen. Natural selection is ruthlessly clear-eyed. That’s what prevents bad mutations from reproducing, and gives favor to the beneficial ones.

If we stick to the physical characteristics of creatures, it’s easy to see how far from arbitrary natural selection is. We can all imagine how selection pressures could fashion an aquadynamic body shape for fish whose ecological niche involves being good swimmers. In each generation of fish, some are born with more suitable shapes and others are doomed to a life of struggle as they push their ungainly bodies through the water. The former are more likely to eat and reproduce; the latter more likely to be eaten and die without offspring. Over time, the species’ body shape improves.

Not all fish survive by being good swimmers. Some, like this stonefish, have slid into an ecological niche that depends on their camoflauge — looking like the surrounding reef, in its case. There, too, it is easy to imagine how natural selection could, in a far from arbitrary fashion, favor those fish who descended with a modification that helped them to lurk undetected.

There are many ecological niches, but natural selection for each niche is ruthlessly non-arbitrary.

Humans may be the weakest large species there is, in terms of physical strength per pound. Our close cousins, the chimpanzees, are about four times stronger, pound-for-pound. Yet we survive. How?

It happens that the ecological niche into which we’ve slid involves using superior intelligence to cooperate with our own kind. Without cooperation, we perish, just as surely as a stonefish with flourescent polka-dots and no venom would perish.

The ability to empathize is a “descent with modification” from mere cooperation that makes cooperation even more effective. Humans whose cooperation is thus enhanced have a survival advantage.

Empathy is the basis of the Golden Rule, which Jesus said summed up the Law and the Prophets.

From an evolutionary perspective, empathy is self-perpetuating. The wish of every teenager is to be paired with “someone who understands me.” In contrast, who wants to marry a sociopath? It’s easy to see how, especially in the formative years of our species, our morality would be honed toward the Golden Rule just as inexorably as a swordfish’s body would be honed for being a fast-swimming predator.

Thus evolution begets morality, at least in our species.

A morality stemming from cooperation and empathy is far from arbitrary. That’s why nearly all cultures’ moral codes share a core that is based on the Golden Rule and its obvious corollaries. (Granted, some cultures are less morally evolved than others and still tolerate things like slavery — an moral-evolutionary way-station that we have thankfully left behind.)

What is arbitrary is a moral code established on the supposed commands of an invisible god. Examples from the Bible are endless, but just to give you the flavor of it…

• The Bible says picking up sticks on the Sabbath is an offense worthy of death (Numbers 15:32-36), but you may use a stick to beat your slave so severely that he can’t get up for almost two full days (Exodus 21:20-21).
• The Bible’s god says that a bride who can’t prove she is a virgin must be stoned to death on her father’s doorstep (Deuteronomy 22:20-21), but the same god gives explicit permission to rape war captives via non-binding “marriages” (Deuteronomy 21:10-14, discussed at length here).

Commands like those, sometimes literally written in stone, are increasingly revealed to be arbitrary, as the optimal shape of real morality is sculpted over time through the natural selection of the memes that form our moral code.

To close, I’d like to recommend this short video of Richard Dawkins responding to the question, “Considering that atheism cannot possibly have any sense of absolute morality, would it not then be an irrational leap of faith … for an atheist to decide between right and wrong?”