I have gradually been compiling a list of modern “natural theology,” that is, those aspects of nature that theologians and religious people see as giving evidence for God. Until 1859, the list’s top item was organismal “design”, but of course Darwin dispelled that. But natural theology—the explication of nature as God’s handiwork—is alive and well, as John Polkinghorne and Nicholas Beale argue in the book I’ve highlighted all week, Questions of Truth:
While science is competent to answer its own questions, questions arise from our experience of doing science whose answering takes us beyond its narrow confines.(p. 12)
Over the past months I’ve made a list of where theologians see evidence for God in nature (not all of these are discussed in P&B):
- The Big Bang: what got it started in the first place? After all a quantum vacuum isn’t nothing.
- Why is science possible at all? The human ability to apprehend truth must be a gift from God, since it couldn’t have evolved (see Plantinga)
- The “unreasonable effectiveness of mathematics” proves that God designed the universe
- Ditto for the existence of physical “laws”
- Only God could have give us the “innate” human sense or morality (see Francis Collins)
- The “fine-tuning” of the universe (that is, the values of physical constants) is evidence for God
- The appearance of humanoid creatures on the planet—creatures capable of apprehending and worshiping a God—is evidence of His handiwork.
Now there are rebuttals of all of these arguments, and I’ve discussed most of them over the past few years. I just wanted to highlight one version of #2, as adumbrated by Polkie and Beale (pp. 81-82 of their book):
Consider human mathematical abilities. For survival, we need not much more than counting and a little elementary geometry. Whence then has come the human ability to study noncommutative algebras and to prove Fermat’s last theorem? I think conventional Darwinian theory is unable to explain this capacity, which requires for its understanding the belief that our environment is not limited to the physical and biological but must also include contact with a noetic realm of mathematical ideas, into which our ancestors were increasingly drawn.
For those who know about the history of evolutionary biology, this argument is remarkably similar to that of Alfred Russel Wallace, who of course proposed the idea of evolution by natural selection in 1858. But, unlike his rival Darwin, Wallace thought that one aspect of biology was inexplicable by natural selection: the human brain. As the quote below shows, Wallace saw the brain as conferring abilities far beyond those needed to survive in our ancestral environments: we can design airplanes, play chess, write music, and fly to the moon (not, of course, in Wallace’s time!). Since natural selection has no foresight, and cannot adapt organisms to their future environments, Wallace saw our large brain as evidence for God, or at least an intelligence in the universe. This quote, reminiscent of Polkie and Beale, comes from Wallace’s “The limits of natural selection as applied to man” (1870).
We see, then, that whether we compare the savage with the higher developments of man, or with the brutes around him, we are alike driven to the conclusion that in his large and well-developed brain he possesses an organ quite disproportionate to his actual requirements — an organ that seems prepared in advance, only to be fully utilized as he progresses in civilization. A brain slightly larger than that of the gorilla would, according to the evidence before us, fully have sufficed for the limited mental development of the savage; and we must therefore admit, that the large brain he actually possesses could never have been solely developed by any of those laws of evolution, whose essence is, that they lead to a degree of organization exactly proportionate to the wants of each species, never beyond those wants — that no preparation can be made for the future development of the race — that one part of the body can never increase in size or complexity, except in strict co-ordination to the pressing wants of the whole.
Wallace’s mistake, which should be obvious, is that we have no assurance that the human brain really is larger than it needs to be, even in the so-called “savages” whom Wallace encountered on his travels. Humans aren’t just gorillas: we can speak, learn, and have sophisticated mental programs for sussing out the thoughts of others and figuring out how to relate to others in small groups. We’ve mastered fire, which according to Richard Wrangham freed up our brain to become more complex under real selection pressures.
And once we have a complex brain, capable of learning, speaking, and working out strategies to hunt and to live in small social groups, it becomes capable of doing things beyond what it evolved for. In other words, chess, math, and building spacecraft are what Steve Gould called exaptations: those features that can be used in a beneficial way but evolved for other reasons. Once the brain crossed a certain threshold of complexity, these things became possible, but those abilities are epiphenomena.
With Wallace, Polkie and Beale see the brain’s ability to do math as something inexplicable by natural selection. Ergo Jebus. But lots of animals have abilities that are similar exaptations. We can train parrots and mynah birds to talk. Is their talking evidence for God? In England, blue tits learned to open milk bottles and drink the milk. They didn’t evolve to do that! Their ability to scan the environment for possible food items, and their possession of a nice bill and ability to wield it dextrously, was an exaptation for drinking milk. So it is with tool-using in animals, from chimpanzees to crows to the cactus finches of the Galapagos: animals can put their already-evolved equipment to new uses. And so it is with the human brain. It hasn’t changed much in the last couple million years, but oh what we have done with it!
Sadly, one of the things we’ve done with it is invent the idea of God, and then, in a curious and invidious recursion, use our ability to conceive of God—and mathematics—as evidence for God himself.
h/t: Andrew Berry for the Wallace quote. I highly recommend his book on Wallace, Infinite Tropics: An Alfred Russel Wallace Collection. It puts together snippets of Wallace’s writings along with commentary by Berry himself. It’s a must-read for evolution aficionados.