“Natural theology” is the discipline that attempts to find evidence for God in the natural world. The most famous example of this doomed exercise is, of course, the erstwhile use of animal and plant “design” as evidence for God’s beneficence.  But Darwin dispelled that in 1859. Earlier, Newton cited the regular and stable orbits of the planets as evidence for God’s intervention. That, argument, too, was refuted by science, and such is the fate of all natural theology.

But the discipline won’t die. It regularly resurfaces via people like Francis Collins and Alvin Plantinga, who claim, respectively, that intuitive human morality (“The Moral Law”) is evidence for God, and that the “fine tuning” of the physical constants of the universe was done by God to allow human life.  Last year I listed several other examples, including the supposed inevitability of human evolution (an argument for God used by Kenneth Miller and Simon Conway Morris), the “unreasonable effectiveness of mathematics”, the very existence of physical laws, and, most bizarrely, the claim of Alvin Plantinga that humans’ ability to perceive truth could not have been instilled in them by evolution, but must reflect a sensus divinitatus given by God. (That sense, of course, has the felicitious side effect of justifying Plantinga’s belief in God and Jesus.)

A new post by Gary Marcus on the New Yorker science-and-technology website “Elements”: “Can science lead to faith?” (free online), reiterates—and criticizes—several recent and noxious eruptions of natural theology from more respectable intellectuals. (Marcus, a former student of Steve Pinker, is now a professor of psychology at New York University.)

The new Natural Theologians  don’t argue for a specific God, like the Christian one, but they do say that evidence points to Something Out There Beyond the Material, knowing very well that the public will take this as vindication of their religious belief.  These god-enabling intellectuals include (indented bits from Marcus’s column):

Jürgen Schmidhuber:

Schmidhuber, in a post on Ray Kurzweil’s A.I. blog, ”In the beginning was the code,” begins with the premise that there “is a fastest, optimal, most efficient way of computing all logically possible universes, including ours—if ours is computable (no evidence against this).” Schmidhuber further elaborates on a “God-like ‘Great Programmer,’ ” and a method by which it would “create and master all logically possible universes.” From this follows what Schmidhuber describes as “Computational Theology,” a component of which is the undeniably heartening claim that “your own life must be very important in the grand scheme of things.” Over all, suggests Schmidhuber, Computational Theology “is compatible with religions claiming that ‘all is one’ and ‘everything is connected to everything.’ ”

I’m baffled by this, and, unwilling to make the effort to master Schmidhuber’s logic (life is too short), I’ll write it off for the nonce as the usual brand of made-up stuff that comprises theology, dressed up in fancy scientific language.

David Eagleman. I’ve discussed Eagleman and his bizarre “philosophy” of “Possibilianism” before (see also here), a philosophy that seems to rest solely on “having the courage to go beyond the data”, i.e., to accept that atheism, agnosticism, and skepticism may well be misguided because there may be some Big Intelligent Forces Out There, including divine beings, aliens, and yes, perhaps even Bigfoot or Nessie. I’m not exaggerating: here’s a quote that Eagleman gave to New Scientist:

So it seems we know too little to commit to strict atheism, and too much to commit to any religion. Given this, I am often surprised by the number of people who seem to possess total certainty about their position. I know a lot of atheists who seethe at the idea of religion, and religious followers who seethe at the idea of atheism – but neither group is bothering with more interesting ideas. They make their impassioned arguments as though the God versus no-God dichotomy were enough for a modern discussion.

What if we were planted here by aliens? What if there are civilisations in spatial dimensions seven through nine? What if we are nodes in a vast, cosmic, computational device? . . .

Consider the enormous “possibility space” of stories that can be dreamed up. Take the entirety of the Judeo-Christian-Islamic tradition as a single point in this possibility space. The eastern religions are another point. Strict atheism is another point. Now think of the immense landscape of the points in between. Many of these points will contain stories that are crazy, silly, or merely wildly improbable. But in the absence of data, they can’t be ruled out of that space.

This is why I call myself a “possibilian”. Possibilianism emphasises the active exploration of new, unconsidered notions. A possibilian is comfortable holding multiple ideas in mind and is not driven by the idea of fighting for a single, particular story. The key emphasis of possibilianism is to shine a flashlight around the possibility space. It is a plea not simply for open-mindedness, but for an active exploration of new ideas.

This could have come from Chopra (note the use of the “computational” trope again). What this philosophy does is free one’s mind from the constraining leash of facts.  Let a million crazy ideas blossom! According to Marcus, Eagleman was threatening to write a book about Possibilianism four years ago, but, mercifully, it hasn’t yet appeared. Marcus comments:

Eagleman is actually dismissive of God-like Great Programmers, or at least those that he knows anything about. He writes, for example, in the New Scientist that “Religious structures are built by humans and brim with all manner of strange human claims—they often reflect cults of personality, xenophobia or mental illness. The holy books of these religions were written millennia ago by people who never had the opportunity to know about DNA, other galaxies, information theory, electricity, the big bang, the big crunch, or even other cultures, literatures or landscapes.” His point is not that he is convinced by any existing religion, but that we should be open-minded to those that have not yet been invented.

Up to a point, there is nothing wrong, scientifically speaking, with Eagleman’s argument. There are some things we don’t know, and it could be, in principle, that some of the things we don’t know pertain to theology. But Eagleman’s argument is weaker than he acknowledges—he implies that if we learn something new about the big bang or DNA, we might somehow discover a deity we had otherwise overlooked, but he offers no specifics. More than that, Eagleman ignores something that is central to modern science: meta-analysis, a set of tools for weighing and combining evidence.

And then Marcus takes Eagleman apart in a discourse about the nature of science that, sadly, must be endlessly repeated to the yahoos who mistake logical possibilities for probabilities:

In the empirical sciences, almost everything is a matter of weighing evidence; outside of geometry, it is rare for scientists to literally prove anything. Rather, the more typical trajectory is to rule out competing theories, and accumulate more and more evidence in favor of particular hypotheses. At some level, all scientists are agnostics, and not just about religion, but about virtually everything. I can see with my own two eyes that you have two feet, but for most things that most scientists have observed, I allow that the evidence is indirect; I believe in black holes not because I have seen one, but because, ultimately, I trust that the authorities who have most carefully thought about these things have reached a consensus that black holes provide the best available explanation for a wide range of phenomena, about the distribution of stars and quasars and other matter throughout the universe. I always allow that some other data could become available, but I take the combined evidence in favor of black holes to be very strong.

Eagleman claims that he is offering something beyond the simple observation, held by agnostics for centuries, that there could be some sort of evidence that’s been left out. Agnosticism “is often an uninteresting stance in which a person simply questions whether his traditional religious story (say, a man with a beard on a cloud) is true or not true,” Eagleman writes. “But,” he boasts, “with Possibilianism I’m hoping to define a new position.” But it’s never really clear what that new position is, or how it differs from agnosticism at a fundamental level. What is clear is that, when it comes to theology, Eagleman is shying away from a technique that forms part of the core of his day job in science: the statistical weighing of evidence.

It’s just so rare to see something like this in a respectable magazine—even the New Yorker, which is notoriously soft on religion—that I’m going to quote Marcus’s last three paragraphs in toto. I credit some of Pinker’s influence here: Steve’s produced a good student, and one who, on his own, can not only dismantle the unwarranted speculations of faith, but also discredit, those who, like Eagleman, make their living enabling religion. (I would argue that Eagleman, who labels himself a “neuroscientist”, is a danger to both rationality and science.)

Marcus:

Scientists and non-scientists alike are still free to believe whatever they want, but the grounds for religion have to be the same as they ever were: faith, not science. Science cannot absolutely prove that there is no divine creator, but the tools of science do allow us to weigh the existing evidence, and assign likelihoods to those hypotheses; by ignoring those tools, Eagleman does science a disservice.

The final strategy of those seeking compatibility between religion and science is to retreat into something that is reminiscent of solipsism, the family of beliefs that allows me to entertain the unfalsifiable yet dubious notion that I might be the only person in the universe (with everyone else just a figment). In a recent book, ”Where the Conflict Really Lies,” the eminent analytical philosopher Alvin Plantinga acknowledges the possibility of evolution, but suggests that random mutations and the like are “clearly compatible with their being caused by God.”

Plantinga argues that Christian believers have a sixth sense, a “sensus divinitatis” that allows them to sense God, with that sense defective or absent in nonbelievers. One could, of course, equally generate an infinite range of similar hypotheses, none scientifically testable, such as “only Zeus believers have a working Zeus sense,” “only ghost believers have a ghost sense,” and so forth, but the possibility of leaping outside the realm of science into a morass of untestable possibilities brings us no closer to a genuine rapprochement between science and religion than we were in the time of Goethe’s “Faust.”

Well, there are of course final redoubts of Natural Theology beyond solipsism—I’ve listed a few above—and there’s always the dumb argument that science and faith must be compatible because there are religious scientists and science-friendly believers. But I love the deft way Marcus dismantles Plantinga’s pretentions.  He doesn’t describe the alternative reason we perceive truth—that natural selection has given us a sensus rationalismus—but that’s a quibble. It’s just so rare to see accommodationism taken apart this way in such a public forum! Kudos to Gary Marcus.