In a recent thread which has attracted a lot of lively comment, Dr. Elizabeth Liddle (a highly respected critic of Intelligent Design who surely needs no introduction here) mounted a vigorous defense of methodological naturalism (“MN”). She began by developing her view of the way science works, in a post on the thread:
[T]he idea that any scientific theory stops science is completely false. Science never stops, and a successfully supported hypothesis is a trigger for more research, not less.
In a subsequent post, Dr. Liddle then proceeded to explain why her view of science necessitates the adoption of methodological naturalism:
Yes, rejection of “MN” is religious, for a very simple reason.
It is not possible to investigate a non-material cause. With “methodological naturalism” we keep on investigating. With “methodological non-naturalism” you may reach a place you have to stop, because you’ve met the “non-material” part.
That stoppage is the religious rejection of “MN”.
I’ll repeat what I just posted elsewhere: “MN” is not a limitation on science. It is quite the opposite. It’s what leads us to keep searching. Rejecting “MN” is what poses limitations on investigation, not the acceptance of MN.
Dr. Liddle elaborated her views in another post on the same thread:
At the point at which you say: “this is not a material cause” you stop investigating. That’s all methodological non-materialism is – it’s stopping when you get to a bit you can’t explain by a material mechanism, and saying “something non-material did this bit”. Methodological materialism is not stopping…
I’d like to make a few comments at this point:
The Contingency Of The Ongoing Success Of Science
It is a contingent matter that we live in a universe where science is possible at all, even if we adopt a fairly minimal definition of “science,” such as: “the systematic tabulation [by intelligent beings] of observed correlations between various kinds of events, in a way that can be described mathematically.” The word “mathematical” is of critical importance here. The observation that the seasons go round in an annual cycle is not science. Nor is the observation that an animal will die if you slash its jugular vein. Both of these observed regularities have been of great practical use to human beings; and indeed, humans could not survive in a world without natural regularities which they could rely on. However, human beings could certainly survive quite well in a world in which they were aware of natural regularities, but were unable to describe them in mathematical language. In fact, for most of human history, that is precisely how we have lived.
I can make the same point in another way. Imagine an alternative world in which there were natural regularities, but in which no natural phenomena could be described by simple equations such as v = u + at (the first equation for uniform accelerated motion), or T^2 = K.(r^3) (Kepler’s third law). The mathematics required to describe natural phenomena in such a world might be too complex for the beings of limited intelligence who happened to live in it; hence science would forever elude them, although their technology might be quite good.
It is also a contingent matter that we live in a universe in which scientific enterprise can go on and on, with no end in sight. One can certainly imagine ways in which science might fizzle out. If we lived in a world of very limited variety, we might be able to fully describe its workings after only 100 years of scientific observations – and after that, we’d have to do something else to keep ourselves amused. Or we might hit a brick wall in scientific research for financial reasons: increased spending on scientific research might yield sharply diminishing scientific returns, so that after discovering the first few scientific laws, we found that the discovery of further laws rapidly became increasingly unaffordable.
So when Dr. Liddle writes that “Science never stops, and a successfully supported hypothesis is a trigger for more research, not less,” my reply is: “Does it have to be that way? I think not.” In 1997, John Horgan wrote a best-selling book titled, The End of Science, in which he addressed the questions: Have all the big questions been answered? Has all the knowledge worth pursuing become known? Interestingly, some of the scientists he interviewed were inclined to answer these questions in the affirmative.
Science, then, may well have an end, whether we like it or not.
All Scientific Explanations Have To Stop Somewhere
The next point to consider is that all scientific explanations have to stop somewhere – otherwise we get an infinite regress of explanations, which doesn’t explain anything. Of course, Intelligent Design critics are perfectly aware of this point, which is why they often raise the objection: “Who designed the Designer?”
So even if Dr. Liddle is correct in maintaining that a non-material cause is a science-stopper, we have to ask ourselves: “Is there a better place at which we should stop asking scientific questions than the point where the Immaterial Designer supposedly makes contact with Nature?” And my answer to that question is: “If you think there’s a better point at which to stop the process of scientific enquiry, then prove it’s better, by demonstrating to me that going beyond that point is scientifically more productive than simply taking the Designer’s alleged point of interface with Nature as a ‘given.’ After all, the proof of the pudding is in the eating.”
Jefferson’s Deity And The Cosmos As A Simulation: How Dr. Liddle Confuses “Non-Material” With “Non-Natural”
Dr. Liddle writes that “It is not possible to investigate a non-material cause.” But even if the Designer of Nature were a material cause, the material processes underlying His acts of design would still elude scientific investigation, simply because He is outside Nature, which means that the workings of His body will forever elude us.
President Thomas Jefferson firmly believed in a Designer of the laws of the universe, even though he believed that the universe had always existed. As he wrote in his letter to John Adams, of April 11, 1823:
… I hold (without appeal to revelation) that when we take a view of the Universe, in it’s parts general or particular, it is impossible for the human mind not to perceive and feel a conviction of design, consummate skill, and indefinite power in every atom of it’s composition…We see, too, evident proofs of the necessity of a superintending power to maintain the Universe in it’s course and order…Some early Christians indeed have believed in the coeternal pre-existence of both the Creator and the world, without changing their relation of cause and effect.
At the same time, Jefferson regarded the notion of an immaterial Deity as utterly nonsensical. He explained his theological position in a letter to John Adams, dated August 15, 1820:
When once we quit the basis of sensation, all is in the wind. To talk of immaterial existences is to talk of nothings. To say that the human soul, angels, god, are immaterial, is to say they are nothings, or that there is no god, no angels, no soul. I cannot reason otherwise: but I believe I am supported in my creed of materialism by Locke, Tracy, and Stewart.
Thus Jefferson envisaged the Deity as an embodied Being, eternally maintaining the universe in its law-governed order. If we let “Physics A” refer to the laws of our cosmos, and “Physics B” denote the laws governing the body of Jefferson’s Deity, which exists outside our cosmos, then it follows that since God is independent of the cosmos, our scientists will never be able to investigate Physics B, and hence will never understand the material processes underlying the Designer of Nature.
Or we can put it another way, and imagine that the entire cosmos – by which I mean everything in reality (inside or outside the visible universe) which is subject to the laws of Nature uncovered by our scientists – is part of a giant simulation, which was created as a science experiment by intelligent beings who are not subject to these laws that they have set up for the simulation. In that case, once again, the Designers of Nature would be material beings, but their materiality would be of a different sort to our own, as they would be subject to completely different laws, which are unobservable to our scientists, as they have no way of accessing the world outside the simulation.
What this tells us, then, is that Dr. Liddle is badly confused when she argues that an immaterial Designer would be a science-stopper. The problem here is not the immateriality of the Designer, but His existing outside the natural order which He has created i.e. the Designer’s transcendence, rather than His immateriality.
Rejection Of Methodological Naturalism Is Not Religious
Even if the rejection of methodological naturalism should prove to be a “science-stopper,” as Dr. Liddle argues, it still would not follow that “rejection of ‘MN’ is religious,” as she claims. In order to show that, one would have to show that rejection of methodological naturalism entails the existence of a Designer Who is also a suitable object of worship. Dr. Liddle has not supplied any argument to this effect. Her use of the term “religious” is pejorative; it demeans the serious philosophical arguments put forward by those thinkers whose vision of science is different from her own.
A Designer Of Nature Can Always Explain More Than Methodological Naturalism
In any case, the scope of phenomena that can be explained by postulating an Intelligent Designer of Nature will always be larger than the scope of phenomena that can be explained within the framework of methodological naturalism. The reason is simple: scientific explanations which accept the constraints of methodological naturalism are bound to take the laws of Nature for granted; whereas scientific explanations which go beyond the constraints imposed by methodological naturalism are capable in principle of explaining the laws of Nature.
The Failure Of Pythagoreanism
I might add that since the laws of Nature are immaterial abstractions, the current practice of halting our scientific explanations when we arrive at the ultimate laws of Nature is tantamount to stopping one’s demand for explanations at something immaterial.
Laws are abstractions. They are even less like material entities than an incorporeal Designer. It is odd that Dr. Liddle has no objection to the enterprise of explaining the world in terms of abstract mathematics, but objects vigorously to explaining the world as the product of a Designer Who wanted to make a cosmos fit for intelligent life. So I would like to ask Dr. Liddle, “Why do you consider an explanation of the cosmos as the product of an immaterial Intelligent Agent to be even worse than an explanation of the cosmos as the product of abstract mathematical entitles like numbers and forms, as Pythagoras thought it was? Surely an immaterial Intelligent Agent can do a better job of generating the cosmos than the number 4.”
Could A Designer of Nature Be Used To Explain Anything And Everything?
A hint as to why Dr. Liddle finds Intelligent Design explanations so unconvincing can be found in a lengthy but interesting comment she made on the same thread, in which she argued that the notion of an immaterial Designer is scientifically vicious, because it could be used to explain anything and everything, and that an explanation of that sort really explains nothing:
OK, let me try this a different way:
If you postulate an invisible intelligent power who can do anything, without leaving any trace of the tools of his/her trade, nor presence, apart from the artefacts s/he leaves behind, there is nothing you can’t explain. Giraffe recurrent laryngeal nerve? No problem, designer wanted it that way. Human female pelvis? Who are we to judge the designer? Hyena reproduction? Well perhaps the designer hated hyenas. Parasites that kill children? Well, perhaps the designer likes parasites more than children. Nested hierarchies? Well, s/he just liked designing that way. No bird lungs for mammals? Well, why shouldn’t s/he try something different, and why shouldn’t s/he keep those bird lungs strictly for the animals that look as though they descended in a particular lineage. In fact, why shouldn’t the designer make the world look as though it evolved?
That’s why a non-material, uncharacterised designer is not an explanation. An explanation that explains everything explains nothing.
However, if you were to postulate an actual material designer, that would be something else – we could actually draw some conclusions about the designer – his/her enthusiasms, his/her strengths, his/her weaknesses, his/her assembly techniques, his/her testing protocols etc.
Then we might have an actual explanation from the ID postulate.
But to do this work, IDists would have to postulate a material designer. Without doing so, none of this work is possible.
That’s the sense in which commitment to non-material causes stops science. Scientists don’t have to believe there are no non-material causes to do science. It’s just that the tools of science can’t investigate them. They are matters of faith, not science.
Immaterial Does Not Mean Inscrutable
Dr. Liddle appears to be setting up a straw man here. There have been theists who have laid great emphasis on what they call the sovereign will of God, to such an extent that they maintain it is not restricted by anything at all. God, they say, can will literally anything. I agree with Dr. Liddle that such a Deity would indeed be utterly capricious, able to explain everything and nothing. If there is a science-friendly Designer, He must be a Being Who is only able to will what is rational.
In her post, Dr. Liddle contends that “An explanation that explains everything explains nothing.” That’s a good argument against “a non-material, uncharacterised designer” but not against a Designer Whose objective is to create sentient and sapient beings, and Who uses His Intellect to accomplish this end in the wisest way possible. What kind of design flaws would we expect such a Designer to tolerate? I would answer: those flaws that cannot be avoided, because they arise as a result of conflicting biological constraints. A Designer would have no choice but to tolerate these.
The Perils Of Picture Thinking
I should point out that the mere fact that we can imagine a better design for an organism does not make it possible in reality. In a previous post of mine, entitled, Of Pegasus and Pangloss: Two Recurring Fallacies of Skeptics, I warned against the dangers of using picture thinking as a guide to possibility, when alleging instances of bad design:
…[T]he problem with this line of thinking is that it conflates two distinct notions: picturability and conceivability. Only the latter can tell us what is possible. Picture thinking cannot….
And that brings me to Pegasus, the winged horse. Is Pegasus possible? Certainly he’s picturable, as the image on the left at the beginning of this post clearly proves. But is he conceivable? Surely not. Just ask yourself a simple question: how does he fly? According to the laws of aerodynamics which obtain in our universe, this should be impossible. Picturability, then, is not a reliable guide to possibility. To argue that a better world is possible simply because we can picture it is to engage in childish thinking.
“Pegasus-thinking”, as I shall call it, is a besetting sin of Darwinists – by which I mean, advocates of an unguided evolutionary process whose principal mechanism is natural selection winnowing random variation. For instance, Professor Jerry Coyne argues in his book, Why Evolution is True (Viking Adult Press, 2009) that the male prostate gland is badly designed because the urethra runs through it, making men liable to enlargement and infection in later life. Aside from the fact that Coyne’s argument open to question on empirical grounds – creationist Jonathan Sarfati asserts that the risk of enlargement appears to be largely diet-related in his 2008 article, The Prostate Gland – is it “badly designed”? – Coyne is essentially arguing that because we can imagine a better design, therefore one is possible; and since we don’t find it in Nature, it follows that Nature is not the work of an Intelligent Creator. The question-begging underlying this argument should be readily apparent.
What About All Those Instances Of Bad Design?
Let’s start with Dr. Liddle’s example of bird lungs. Bird lungs originally evolved in order to enable the ancestors of birds to cope with very low oxygen levels, which were prevalent between 175 and 275 million years ago (see here). The reader might be asking: why don’t mammals have lungs like this? That’s a very good question. The (scientifically falsifiable) prediction I would make is that mammals would incur a severe fitness cost if they did. It should be easy enough for scientists to test this prediction by manipulating the genes of developing mammals to give them avian lungs, and then seeing how this impacted on their fitness. I am highly skeptical of the Darwinist “explanation” that evolution just happened to find a better solution for birds than for mammals. To me, that account explains nothing at all. It’s what I’d call a real science stopper.
But what about that most comical of anatomical imperfections, the laryngeal nerve of the giraffe, cited by Dr. Richard Dawkins as excellent evidence for Darwinian evolution? Now, if the laryngeal nerve were just involved in controlling the larynx, then Dawkins might have a good point. The laryngeal nerve comes down from the brain and loops around the arteries near the heart and then goes back up to the larynx. In the giraffe, this seems like particularly bad design. However, the laryngeal nerve actually has several branches all along its length that go to the heart, esophagus, trachea, and thyroid gland. Thus it is involved in a whole system of control of various related organs. It would be very unintelligent to have a single nerve, controlling only the larynx. It would be more intelligent to have it control a lot of related systems all along its length (see this article.) Hence the laryngeal nerve, far from being a problem for intelligent design, actually vindicates it.
Creationist Dr. Jonathan Sarfati makes the same point in a recent article entitled, Recurrent Laryngeal Nerve, and adds that its position may have something to do with the development of the animal as an embryo:
Dawkins considers only its main destination, the larynx. In reality, the nerve also has a role in supplying parts of the heart, windpipe muscles and mucous membranes, and the esophagus, which could explain its route.
Even apart from this function, there are features that are the result of embryonic development – not because of evolution, but because the embryo develops from a single cell in a certain order. For example, the embryo needs a functioning simple heart early on; this later descends to its position in the chest, dragging the nerve bundle with it.
This is a fruitful Intelligent Design hypothesis, and a falsifiable one. If it is wrong, we should know soon enough.
Finally, a recent article by Dr. Jerry Bergman, entitled Recurrent Laryngeal Nerve Is Not Evidence of Poor Design, in Acts & Facts 39 (8): 12-14, concludes:
The left recurrent laryngeal nerve is not poorly designed, but rather is clear evidence of intelligent design:
- Much evidence exists that the present design results from developmental constraints.
- There are indications that this design serves to fine-tune laryngeal functions.
- The nerve serves to innervate other organs after it branches from the vagus on its way to the larynx.
- The design provides backup innervation to the larynx in case another nerve is damaged.
- No evidence exists that the design causes any disadvantage.
The arguments presented by evolutionists are both incorrect and have discouraged research into the specific reasons for the existing design.
What about the female human pelvis? We now know that Homo erectus females had large, wide pelvises in order to deliver large-brained babies, which meant that Homo erectus infants became independent far more quickly than modern human infants. However, the average brain size of Homo erectus was considerably smaller than that of Homo sapiens, and further evolutionary widening of the pelvis to accommodate larger-brained Homo sapiens infants may have severely hampered women’s mobility while walking. What happened instead was that Homo sapiens infants were born immature, which in turn meant that they required an extended period of parental care. Once again, we see trade-offs being made because of conflicting biological constraints. Blaming the Designer for this is like blaming Him for not being able to make a square circle. It’s simply childish.
There are parasites which are dedicated to attacking people: the malaria parasite, for instance. But what we continually need to remind ourselves is that we don’t know all the facts about the original condition of these seemingly malevolent organisms, as well as their subsequent development. Until we do, we are in no position to sit in judgment on the Designer.
For instance, according to a recent press release by the National Science Foundation, modern malaria parasites began to spread to various mammals, birds and reptiles about 16 million years ago. Malaria parasites may jump to new, unrelated hosts at any time, decoupling their evolution from that of their hosts. The ancestors of humans acquired the parasite 2.5 million years ago – very close to the time when humans first appeared. However, according to Dr. Robert Ricklefs, one of the biologists who conducted the recent research into the origin of the malaria parasite, “Malaria parasites undoubtedly were relatively benign for most of that history, becoming a major disease only after the origins of agriculture and dense human populations.”
An Alternative Intelligent Design Hypothesis?
In the post I quoted above from Dr. Liddle, she remarked:
…[I]f you were to postulate an actual material designer, that would be something else – we could actually draw some conclusions about the designer – his/her enthusiasms, his/her strengths, his/her weaknesses, his/her assembly techniques, his/her testing protocols etc.
Then we might have an actual explanation from the ID postulate.
So here’s my invitation to Dr. Liddle: if you really find the notion of a pure spirit philosophically incoherent, why not postulate a Jeffersonian Designer, who is subject to material as well as logical constraints? After all, materialistic Deism is a perfectly respectable worldview, with a long history. Look at the fossil record, examine the imperfections in living things, and tell me what you can deduce about the physical limitations of your Designer. The Intelligent Design movement is a very broad tent, and you’re more than welcome to conduct research along these lines. For the fact is that scientific arguments alone cannot rule out the existence of a Jeffersonian Designer. Only metaphysical arguments could do that. However, Intelligent Design proponents are not tied to any particular metaphysical view, as ID is a scientific program.
Over to you, Dr. Liddle.