Doctor Pangloss rides again

An article in The Guardian by Mark Vernon (Mark’s blog) reminded me of a character in one of Voltaire’s works, but I’ll get to that later.

First, a legitimate point from Vernon to sugar the pill.  Vernon takes issue with Dawkins’ open and frank attack on religious dogma in his new television series, The Genius of Charles Darwin.

Most Christians find accommodation with evolution, and welcome it. “Darwinism appeared, and, under the guise of a foe, did the work of a friend,” wrote Aubrey Moore, the late-Victorian Anglo-Catholic theologian. Why not celebrate that? Wouldn’t it be a better strategy than giving creationism prime time?

I think that’s a reasonable question, and one that is addressed by Dawkins in Chapter 8 of his book, The God Delusion, titled “What’s wrong with religion?  Why be so hostile?”  and in the chapter that follows, which is specifically about the effects on childhood and education.  If Mark Vernon has watched Dawkins’ television series (about which he made the above comment), he will have seen, in Part 1, religiously motivated objections to science teaching in the classroom, made by children who have been taught by their parents to believe that the facts are in a book, and that the contents of the book are absolute truth and override any countervailing evidence.  Clearly somebody has been giving creationism prime time in the lives of those children and in their developing minds.

Vernon will also have seen, in Part 3, the science teachers of the same school, when asked why they don’t challenge religious dogma when it is raised by children in the science classroom, argue that they are only presenting the evidence, and “For some students, truth isn’t something they see in science.  Even though our emphasis is on ideas and evidence to support these ideas, a lot of students have a religious narrative that’s very important to them. It’s a very important part of their life.”  So Dawkins’ point, made in his book and this TV series, is that cultural relativism in the name of diversity destroys the value of education.  Still, there can be reasonable disagreement on tactics.

Vernon quickly gets down to his second point, that ‘The science of evolution is becoming much more interesting than a black and white presentation of it allows. Moreover, for believers, it is starting to look far less bleak than the phrase “survival of the fittest” implies.’  What can he mean?

Such directions are explored in a new collection of essays by leading evolutionists, philosophers and theologians in a book, entitled The Deep Structure of Biology. The central issue under discussion in this case is that of evolutionary convergence. The editor of the book is also the great champion of convergence, namely the Cambridge paleontologist Simon Conway Morris.

The work of Conway Morris, and now many others, is showing that evolution keeps coming up with the same solutions to natural problems. One of the better-known examples is that sabre-toothed cats. They evolved on at least three different occasions along independent Darwinian paths. And yet they look almost exactly the same. Dozens of examples of convergence have now been documented across a wide variety of biological phenomena, from animal and plant physiology to molecular biology.

Conway Morris is a paleontologist, a Christian and a teleologist.  Teleology is just a fancy name for purpose. Conway Morris believes that evolution is a tool of God’s masterplan to construct the human race and (perhaps) creatures on other planets that closely resemble humans.  At the outset of his career, he made a meticulous and beautiful study of the Burgess Shale fauna, which was described by fellow paleontologist Stephen Jay Gould in his work, Wonderful Life (1989).  But where Gould saw “radical contingency”, a glimpse of a world of might-have-been, a number of diverse and now-extinct phyla, and an indication that evolution could easily have followed a very different path, Conway Morris now sees certainty.  In The Crucible of Creation: The Burgess Shale and the Rise of Animals, he argues that the Burgess Shale fauna could all be classified into modern phyla–a conclusion that required a complete reversal of his own earlier opinions.   Changing your mind on evidence is a good thing, of course, but how strong is Conway Morris’s evidence?  Well, it’s thin, not to put too fine a point on it.  Gould had said:

But if I could rerun the tape of life from the origin of unicellular organisms, what odds would you give me on the reevolution of this complex and contingent insect-flower system? Would we see anything like either insects or flowers in the rerun? Would terrestrial life originate at all? Would we get mobile creatures that we could call animals? Fine-scale predictability only arises when you are already 99 percent of the way toward a particular result — and the establishment of this 99 percent lies firmly in the domain of unrepeatable contingency.”

This argument is radical and controversial.  However most biologists who think Gould went too far (including Dawkins and Maynard Smith) think he overlooks something Daniel Dennet calls “good tricks in design space”.  Some designs occur again and again because, with the available tools, they’re pretty good solutions.  So we get eyes evolving forty times or so, the hydrodynamic shape of the dolphin closely resembles that of the shark, creatures closely resembling African carnivores developed in two marsupial families in Australia and South America.  Convergent evolution.  But the reason biologists disagree with Gould’s radical contingency isn’t because they don’t think chance plays a big role in evolution.  They’re in agreement with him on that.  And they certainly don’t disagree (at least, most of them don’t) because they think the evolution of humans was inevitable.  Plausible, yes, inevitable,  no.  The fossil record is pretty clear on this: true bipeds are very rare, and intelligence is very rare.  All paleontologists are aware of this.

But Conway Morris manages to ignore it or discount it. It seems that Gould’s radical (and quite possibly flawed) argument shocked Conway Morris so much that he has devoted his whole career to expunging his earlier thoughts on the Burgess Shale and arguing for its exact opposite.  It seems that the suggestion that it’s possible that humans might not have evolved offends his teleological sensibilities.

Conway Morris starts with what one might call, if the name weren’t such an understatement, a radical teleological assumption: evolution inevitably gives rise to intelligent human-like animals.  His arguments are the evidence for convergence in nature such as the carnivore-like marsupials, arm-waving and…um, that’s it.  His teleological fallacy is dealt with more than adequately in this review of Conway Morris’s Life’s Solution: Inevitable Humans in a Lonely Universe (2003) by PZ Myers.  It’s shockingly bad science to make your mind up that man was created in God’s image and then go hunting for evidence you can shoehorn into that view.

So Dawkins should give air time to the religious who let their beliefs compromise their science, rather than make a case against the injection of religious belief into the classroom?  Perhaps, but I don’t think that’s what Mark Vernon intended.

He continues:

Convergence raises the possibility of directionality in evolution. This is anathema to the old school. Strictly speaking, even to talk of adaptations being advantageous is to risk a false sense of teleology. The sense of “advantage” only comes because we have hindsight. As Stephen Jay Gould put it: according to this interpretation of evolution, if you re-ran the “tape of life”, life would look very different.

Convergence challenges this, because in a way, evolution has already re-run the tape of life several times, and it looks strikingly similar. The implications that might be drawn from convergence is what Conway Morris’ new book explores. One of the essays, entitled Purpose in a Darwinian World, is written by the philosopher of evolution, Professor Michael Ruse.

Ruse points out that in one way, convergence is not at all surprising. Evolution does not just work on the basis of random mutations. It also works because those random mutations find niches to occupy in the environment. To put it another way, Darwinian processes “design” organisms to exploit aspects of the natural world.

Ruse reminds readers that some Darwinians believe that evolution itself creates niches, rather than discovers them. However, that can’t always be the case. For example, lungs need the niche of an atmosphere to evolve: the evolution of lungs doesn’t create air.

However, the phenomenon of convergence is used to take the possibility of directionality a step further. For what happens if you consider not only elements such as air, water and land to be environmental niches that Darwinian processes can exploit, but elements such as culture and intelligence too? The old school believes that evolution itself creates the niches of culture and intelligence. But what if instead of creating these niches, evolution is exploring pre-existing realities that in this respect can be thought of as analogous to air, water and land?

Typically, we picture a lineage as radiating to fill all available niches in the ecology in which its features give it an advantage.  To extract an ounce of comfort from this, the teleologist must suck very hard, and avoid reading scientific textbooks (being a philosopher helps, too).  The teleologist here clearly wants us to ask: “who created the niches?”

But this is mere sleight-of-hand.  And Vernon quickly shows his hand so we’re left in no doubt:

It sounds pretty speculative, until you consider, say, mathematics. At least some human’s brains are capable of doing mathematics. Perhaps some other animal’s brains are too. But is mathematics created or discovered? It seems more natural to think of mathematics as existing regardless of the presence of human beings, as, say, the laws of nature presumably exist in the universe too. So maybe the evolution of culture and intelligence are not just by-products of humankind’s evolution as a social animal. Perhaps, they are also ways of discovering and exploring pre-existing realities. Conway Morris himself has tentatively suggested that the brain could be thought of as an evolving “antenna” that detects mentality which is itself independent of human intelligence.

Well he got one thing right: the human brain has evolved to be intrinsically teleological.  We look for purposes, pattern, structure.  When explaining how a system works, we speak in intentional terms.  We use intentional language: “My computer didn’t like that,” even though we know that the computer is merely a collection of chips and has no opinion at all. Some other animals appear to have similar capacity, though experiments are dogged with the difficulty of distinguishing precisely how an animal solves a problem that, for a human, we know would involve a teleological assumption.  Animals cannot tell us, so we have to devise our experiments carefully.  Do my cats assume that I intend to feed them if I approach their bowl?  Probably, but it would be difficult (but not impossible) to rule out a conditioned response.

Now there is a legitimate question over whether mathematics is a “pre-existing reality” but if it is (I happen to think it is), so what? Gravity, neutrons, the planet Neptune, and gamma radiation are pre-existing realities.  If we develop space travel and colonize other worlds, are we going to say that they were put there so that we could colonize them, a niche waiting for some latterday wagon train to come by and stake a claim?  Pre-existing realities do not support the teleological assumption.

The greatest celestial teleologist of Voltaire’s day was the great philosopher Gottfried Leibniz, who in his work, Essays of theodicy on the goodness of God, the freedom of man and the origin of evil, argued that “God has chosen the best of all possible worlds”, and “cannot but have chosen the best.”  Indeed some people reading his ideas feared that Leibniz had gone far too far, and boxed God in so that he had no free will.  Others felt that the characterization of our world as “the best of all possible” ill reflected their own experience and knowledge of history.  For this reason, he was famously satirized in Voltaire’s work, Candide, as Doctor Pangloss.  Doctor Pangloss, the hero Candide, and his beloved Cunégonde undergo various indignities, calamities and outright disasters, up to and including the very real Lisbon earthquake which struck on All Saints Day, 1755 and killed tens of thousands and destroyed 85 per cent of the buildings.  After each fresh mishap, the good Doctor, a man of the Leibnizian persuasion, takes comfort from the belief that “all things are for the best, in the best of all possible worlds”.

One example will do:

“It is demonstrable,” said he, “that things cannot be otherwise than as they are; for as all things have been created for some end, they must necessarily be created for the best end. Observe, for instance, the nose is formed for spectacles, therefore we wear spectacles. The legs are visibly designed for stockings, accordingly we wear stockings. Stones were made to be hewn and to construct castles, therefore My Lord has a magnificent castle; for the greatest baron in the province ought to be the best lodged. Swine were intended to be eaten, therefore we eat pork all the year round: and they, who assert that everything is right, do not express themselves correctly; they should say that everything is best.”

And so, it struck me this evening, along comes Mark Vernon, our latterday Doctor Pangloss.  Mathematics was created for an end: so that we will develop complex brains and become mathematics teachers.  I’m not sure that characterization is entirely unfair, though I acknowledge Mark Vernon’s position as an agnostic, which would seem to rule out a dogmatic adherence to teleology.  However, I suspect that Doctor Dawkins feels he has better things to do than to revisit arguments he disposed of two decades ago in Blind Watchmaker.

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