Monday, December 5, 2011

Believing Bullshit chpt 2

“BUT IT FITS!” AND THE BLUNDERBUSS

“But It Fits!” is one of the most popular strategies for immunizing beliefs against refutation. In fact, “But it fits!” does double duty. Not only is it a great immunizing strategy, it can also be used to create the illusion that a ridiculous belief system is not, after all, ridiculous, but at least as well confirmed as its rivals. I’ll explain how “But It Fits!” works by means of a particularly impressive example: Young Earth Creationism.

Young Earth Creationism


Young Earth Creationism is a theory based on a literal reading of the Old Testament. Young Earth Creationists maintain that the entire universe is less than ten thousand years old (a typical estimate is about six thousand years old). They claim that the universe, the Earth, and every living species were created literally as described in Genesis, over a period of six days.

So, according to Young Earth Creationists, the theory of evolution, which says that new species can evolve, and have been doing so over many millions years, is false. So are current cosmological theories that say that the universe came into existence several billions of years ago (between 13 and 14 billions years ago).

Young Earth Creationism is popular. Polls fairly consistently indicate that around about 45% of U.S. citizens believe it. Nor is it restricted to the uneducated. A 1972 Gallup poll suggested that about a third of U.S. graduates believe we are all descendents of Adam and Eve. For many, Creationism is a moral crusade. According to H. M. Morris, a leading proponent,

Evolution is the root of atheism, of communism, nazism, behaviourism, economic imperialism, militarism, libertinism, anarchism, and all manner of anti-Christian systems of belief and practice.

Young Earth Creationists typically see themselves fighting a battle over the souls of coming generations, and are particular keen to have their beliefs taught in schools.

Extraordinarily, not only do many millions of Americans believe the universe is only about six thousand years old, many also believe that Young Earth Creationism is good science. They consider the Biblical account of creation to be at least as scientifically well-confirmed as the theories of evolution and a billions-of-years-old universe.



How, you may be wondering, can any sane, reasonably well-educated person believe that Young Earth Creationism is just as scientifically credible and well-confirmed as its more orthodox scientific rivals? After, isn’t there overwhelming empirical evidence against Young Earth Creationism? What about the fossil record, which reveals the species currently living on this planet have evolved from common ancestors over many millions of years? And of course, you might well add that the fossil record is merely one piece of evidence for the theory of evolution. The theory is also powerfully confirmed by discoveries in genetics (indeed, an overwhelming case for evolution can now be made even without appealing to the fossil record at all) . Surely there’s also a mountain of evidence that the universe is much older than ten thousand years. For example:

What of the light from distant galaxies, which, given the speed of light, would have taken hundreds of millions of years to get here (and even that from stars within our own galaxy can take tens of thousands of years to arrive)?

What of the movement of tectonic plates, which we know to be very slow, but also have succeeded in separating the Atlantic coasts by thousands of miles?

What of the seasonal layers of ice found at the Poles, the drilled out cores of which reveal a seasonal history dating back hundreds of thousands of years?

What of radio-carbon and other forms of dating which reliably date objects to be much older than Young Earth Creationists claim they must be?

What of the chalk beds revealed by the white cliffs of Dover, which are over hundreds of metres deep? Under a microscope, chalk is revealed to be made of the compressed shells of tiny micro-organisms. They died, their shells sank to the bottom producing a sediment that finally solidified into the chalk beds we see today. At current rates of deposit, the deepest beds would have taken tens of millions of years to produce. According to Young Earth Creationists, the entire universe is less than one thousandth as old as that.

We might go on and on. There’s hardly a branch of science that doesn’t supply us with evidence that the universe is vastly older than Young Earth Creationists claim it to be. These sciences together provide a consistent, coherent and increasingly detailed history of life, the Earth and the Universe that is almost entirely at odds with the Biblical account.

How, then, do so many Young Earth Creationists convince themselves that their theory is not falsified by the empirical evidence? How are they persuaded that it is in fact scientifically confirmed? Let’s begin by looking at how they approach the fossil record.

The Flood theory

Most Young Earth Creationists appeal to one or more catastrophes to explain geological features – mountain ranges, sedimentary layers, etc. – that might otherwise seem far older. There’s nothing wrong with catastrophe theories as such. Even orthodox scientists suppose catastrophes – comet strikes, volcanic eruptions, floods, and so on – have played an important role in shaping this planet and the life on it. According to most contemporary Young Earth Creationists, however, the key catastrophe involved in shaping our contemporary landscape was the Biblical Flood: the flood on which Noah famously floated his Ark. They believe that Old Testament story is literally true. Noah really did build an Ark onto which he was instructed by God to put seven mated pairs of every kind of clean kind of animal and every kind of bird (Genesis 7.2). The waters then rose, drowning the rest. The current inhabitants of the land and sky are the descendents of those who boarded the Ark.

So how does the Flood supposed to account for various geological features, such as the fossil record? It’s claimed that, when the waters rose, they produced huge amounts of silt and mud. This material settled and solidified, eventually forming many of the sedimentary rock layers we find today. Most of the fossils we find within these layers are fossils of creatures drowned by the rising waters. The Flood also explains other geological features, such as the Grand Canyon, which was carved out when the flood waters subsided.

Perhaps you are wondering why creatures are not buried randomly within the sedimentary layers, but arranged in a very specific order? Why, if the Flood theory is true, do we never find the fossils of large mammals within the same layers as dinosaurs? Why do the lower layers contain fossils of only simple sea creatures? Why does man only appear in only the very topmost layers? Why, if they were all buried by the same catastrophic flood, aren’t their remains largely jumbled up?

Young Earth Creationists have their answers. They say we would expect the simple sea creatures living at the bottom of the ocean to be buried first. Birds would be restricted to the higher layers as they would be able to fly from the rising waters. Mankind, being the smartest, would probably have found ways to avoid being drowned until the last moment, so it is not surprising we find human remains only in the top layers. We should also expect to see some order in the fossil record due, for example, to the fact that different ecological zones were submerged at different times, and also because of the different rates at which the corpses of different species bloat and then sink. “So you see?” say Young Earth Creationists. “The fossil record is, after all, consistent with our theory!”

We might say, in reply “But these moves made by Creationists only postpone their difficulties, as they generate a myriad of further puzzles. What about flightless birds, such as penguins and ostriches, which would not have been able postpone being drowned? Why do their fossils never show up in layers lower than other birds? Why do we find sharks, but no dolphins in the lower sedimentary layers, given they occupy similar ecological zones? Surely both would have been buried in the early stages of the Flood? we could go on, and on, and on, citing a mountain of fossil evidence that contradicts the Flood theory.” However, Young Earth Creationists have in some cases constructed Flood-friendly explanations for these observations, and continue to work on developing Flood-friendly explanations for the rest.

Of course it’s not just the fossil record that generates puzzles for Young Earth Creationism. Let’s think for a moment about the logistics of Noah’s expedition. Genesis 16.2 says the Ark was 300 x 50 x 30 cubits – that’s about 460 x 75 x 44 feet. Not a particularly large vessel (a cross section of 75 by 44 feet is, coincidentally, similar to that of my four-bedroomed Victorian terraced house). How did at least two of every kind fit aboard this rather small vessel? Noah didn’t just need specimens of modern creatures such as African elephants, rhinos and giraffes. If dinosaurs were drowned in the Flood, then Noah must have put at least two of each species of dinosaur on board his Ark. Young Earth Creationists accept this. But then how did he get two T. Rex, two Stegosaurs, two Brontosaurs, and so on, safely aboard? And these aren’t even the very largest dinosaurs. What about, for example, two Argentinosaurs, at 120ft long and 100 tons each?

Other questions arise. What did Noah feed his creatures during their voyage? How did Noah round up the known 900,000 insect species from around the planet, and how did he ensure they weren’t trodden on during the voyage? Also, how did Noah acquire polar bears from the Arctic and possums from Australia – how did they cross the vast oceans and continents to reach the Ark?

However, Young Earth Creationists are not so easily defeated, and have constructed answers to all these and other obvious questions about Noah’s voyage. For example, the website of Christian Information Ministries suggest that Noah did not need at least two of every named species of dinosaur, merely two of every “kind” (whatever that is, exactly):

…some creationists believe there may have been far fewer animals if Noah only took on board pairs of "kinds" as the word is used in Genesis 1. God created these "kinds" with potential for rich genetic diversity.

Creation Ministries International endorses this explanation, adding that:

Although there are about 668 names of dinosaurs, there are perhaps only 55 different ‘kinds’ of dinosaurs.


The same source also suggest that Noah did not need full-sized adult specimens – young examples would do:

Furthermore, not all dinosaurs were huge like the Brachiosaurus, and even those dinosaurs on the Ark were probably ‘teenagers’ or young adults. Indeed, dinosaurs were recently discovered to go through a growth spurt, so God could have brought dinosaurs of the right age to start this spurt as soon as they disembarked.


So how did Noah feed all his creatures while they were at sea? Christian Information Ministries suggests they hibernated:

How Noah and his small family could have cared for this large menagerie is unknown, not to mention the sanitation problem! What we must remember is that this event, i.e., the Flood, had supernatural elements. For instance, the animals came to the Ark against their natural instincts (Gen. 6:20). It is therefore reasonable to assume, as some creationists do, that the animals' metabolism may have been slowed down during their confinement, even to the point where some of the animals may have gone into a state of hibernation.

Of course, once we allow “supernatural elements” to play a role, we could just say that God shrank the dinosaurs to pocket size during their journey. That would also deal with many of these problems.

How did Young Earth Creationists explain how polar bears and possums made it all the way to Noah’s Ark across the great oceans? According to Ken Ham and Tim Lovett at Answers in Genesis, there were no separate continents at that time. There was a single continent that the Flood subsequently broke apart, as they here explain:

As even secular geologists observe, it does appear that the continents were at one time “together” and not separated by the vast oceans of today. The forces involved in the Flood were certainly sufficient to change all of this.

Really? The forces were sufficient to push vast continents around the face of the planet, but not enough to sink a wooden vessel with a cross section of 75 by 44 feet? I guess God must have somehow protected the Ark from these extraordinary forces.

Even setting aside Ark logistics, the Flood theory raises a host of other questions, such as where did all the water sufficient to cover the Earth’s great mountain ranges go? Answer: there were no great ranges at that time – they were created by the Flood. Because the surface of the Earth was relatively flat, there was, and still is, more than enough water to cover the land, as Ham and Lovett also explain:

Simply put, the water from the Flood is in the oceans and seas we see today. Three-quarters of the earth’s surface is covered with water.

So how did creatures get back to their respective newly-created continents after the Ark was finally deposited on the mountains of Ararat (Genesis 8.4)? The marmosets could hardly have walked and swum half way round the world, across the Atlantic Ocean, to the Amazonian rainforests where they now dwell. I guess Noah must have dropped the marmosets off in South America and the possums off in Australia as the waters receded (though how, then, did the Ark end up deposited high on the mountains of Ararat?) Or perhaps Noah built them rafts.

So you see? Young Earth Creationists can deal with very many of these questions! Admittedly, they don’t have all the answers – and don’t claim to. But, as they correctly point out, who does? Even orthodox science faces questions it is not currently able to answer, and perhaps never will.

Explanations such as those outlined above are continuously being developed and refined by people describing themselves as “scientists” in multi-million dollar “research institutes” dedicated to the pursuit of something called “creation science”. These “scientists” insist that, far from falsifying Young Earth Creationism, the empirical evidence is broadly consistent with it. Young Earth Creationism, they maintain, fits the evidence at least as well as its orthodox scientific rivals. Surely, they add, good science is all about developing theories to fit the evidence. But then, because they are developing their theory to make it fit the evidence, what they practising is good science. Moreover, if theories are confirmed to the extent that they fit the evidence, then Young Earth Creationism, developed and refined in these ways, is as well confirmed as its rivals.

“Dogs are spies from the planet Venus”

To summarize: Young Earth Creationism is supposedly:

(i) not falsified by the empirical evidence, but actually consistent with it.
(ii) good science
(iii) at least as well confirmed as the theory of evolution, etc.

All three of these claims are false. To begin to see why, let’s start with an analogy.

Dave believes dogs are spies from the planet Venus. He views any canine with great suspicion, for he believes they originate on Venus, and are here to do reconnaissance. Dogs, Dave supposes, secretly send their reports back to Venus, where the rest of their fiendishly cunning alien species are meticulously planning their invasion of the Earth. Their spaceships will shortly arrive from Venus to enslave the human race and take over the world.

Unsurprisingly, Dave’s friends think he has a screw loose, and try to convince him that dogs are comparatively benign pets, not cunning alien spies. Here’s a typical example of how their conversations with Dave go.

DAVE: It’s only a matter of weeks now! The spaceships will arrive and then you’ll wish you’d listened to me. We must act now – let the government know!
MARY: Look Dave, dogs are pretty obviously not space invaders, they’re just dumb pets. Dogs can’t even speak, for goodness sake, let alone communicate with Venus!
DAVE: They can speak – they just choose to hide their linguistic ability from us. They wait till we leave the room before they talk to each other.
PETE: But Venus is a dead planet, Dave. It’s horrifically hot and swathed in clouds of acid. Nothing could live there, certainly not a dog!
DAVE: Dogs don’t live on the surface of Venus, you fool - they live below, in deep underground bunkers.
MARY: But then how do Earth-bound dogs communicate with their allies on Venus? I’ve got a dog, and I’ve never found an alien transmitter hidden in his basket.
DAVE: They don’t use technology we can observe. Their transmitters are hidden inside their brains!
MARY: But Pete is a vet, and he’s X-rayed several dog’s heads, and he’s never found anything in there!
PETE: In fact, I once chopped up a dog’s brain in veterinary school – let me assure you Dave, there was no transmitter in there!
DAVE: You’re assuming their transmitters would be recognizable as such. They are actually made of organic material indistinguishable from brain stuff. That’s why they don’t show up on X-Rays. This is advanced alien technology remember – of course we cannot detect it!
MARY: But we don’t detect any weird signals being directed at Venus from the Earth.
DAVE: Of course, we don’t – like I said, remember this is advanced alien technology beyond our limited understanding!
PETE: How do dogs fly spaceships? They don’t even have hands. So they can’t hold things like steering wheels and joy sticks.
DAVE: Really, Pete. Think about it. You are assuming that their spacecraft will be designed to be operated by human hands. Obviously they won’t. They’ll be designed to be manoeuvred by a dog’s limbs, mouth, tongue and so on.

You can see how this conversation might continue ad nauseum. Mary and Pete keep coming up with evidence against Dave’s belief that dogs are Venusian spies. But, given a little ingenuity, Dave can always salvage his core theory. He can continually adjust and develop it so that it continues to “fit” the evidence.

Confirmation - the “fit” model


Clearly, Dave’s theory about dogs is not well-confirmed by the available evidence. The first moral we can extract from this example is that, whatever is required in order for a theory to be well-confirmed, rather more is required than achieving mere consistency with that evidence.

As Dave illustrates, any belief, no matter how ludicrous, can be made consistent with the available evidence, given a little ingenuity. Believe that the Earth is flat, that the Moon is made of cheese, that the World Trade Centre was brought down by the U.S. Government, are that George W. Bush is really Elvis Presley in disguise? All these theories can be endlessly adjusted and developed so that they remain consistent with the available evidence. Yet they are not well-confirmed.

The claim that Young Earth Creationism is at least as well confirmed as its scientific rivals relies crucially on what we might call the “fit” model of confirmation. According to the “fit” model, confirmation is all about “fitting” the evidence. But more is required for genuine confirmation than mere “fit”, which any theory, no matter how absurd, can, in principle, achieve. So what else is required?

Genuine confirmation

While scientists and philosophers of science may disagree on the details, most would sign up to something like the following.

In order for a theory to be strongly confirmed by the data, at least three conditions must be met. The theory must make predictions that are:

(i) clear and precise,
(ii) surprising, and
(iii) true

Let’s unpack these conditions.

Prediction

First off, let’s say a little more about predictions. To be strongly confirmed, your theory must allow for the derivation of predictions about the observable. So, for example, from the theory that water freezes below zero degrees centigrade, we can derive the prediction that if the temperature of this particular sample of water is reduced to below zero, it will freeze. From the theory that all swans are white, we can derive the prediction that the next swan we observe will be white. And (a slightly more complex example), from Newton’s theory of universal gravitation we can derive the prediction that the planet Uranus will move in a smooth elliptical orbit around the sun.

Notice that, very often, the derivation of a prediction from a theory involves the use of certain auxiliary hypotheses. The reason the above example involving Newton’s theory is more complex is that it does not by itself directly entail that Uranus will have a smooth elliptical orbit. In order to derive that particular prediction, we have to help ourselves to certain auxiliary hypothesis, including the auxiliary hypothesis that there are no other bodies exerting a gravitational pull on that planet (which might distort Uranus’ elliptical orbit).

The fact that we can derive from a theory a prediction about the observable means that the theory can, in principle, be tested. We can check and see whether the prediction is true. Let’s suppose the prediction is true. What follows?

Notice that confirmation is a matter of degree: theories can be more or less well confirmed by a piece of evidence. For example, observing a single white swan provides some confirmation that all swans are white, but not very much. So what is required for strong confirmation?

Clarity and precision

Suppose the prediction I derive from my theory is ambiguous and vague. Then it won’t be difficult to interpret it in such a way that, whatever is observed, I can say, “Hey, my prediction came true!”

Predictions made by psychics often have this character. Take the claim that you will “shortly meet a tall, dark and handsome stranger”. What does “shortly” mean? Today? This week? This year? Is five foot eleven “tall”? Does brown hair qualify someone as “dark”? What counts as “handsome”? Because of the usually rather ambiguous nature of a psychic’s prediction, it’s easy to interpret it in such a way that it comes out as “true”. The same is true of the prophecies of Nostradamus, the medieval seer whose cryptic prose supposedly predicts all sorts of dramatic events, such as the rise of Hitler, and 9/11. Nostradamus’ writing is so vague that, when some major event happens, it’s not difficult to find a passage that “predicts” it (I look more closely at the work of Nostradamus in the conclusion to this book).

For strong confirmation, we need to be able to derive from our theory predictions that are clear and precise, and one very obvious way in which they can do this is if they concern mathematically quantifiable and objectively measurable phenomena. The claim that every dog will be “heavy-ish” is so vague as to be unfalsifiable, while the claim that every dog weighs more than five kilos can easily be falsified with the aid of a scale.

Surprisingness

However, even a clear, precise and true prediction is not enough to guarantee strong confirmation. A further, key ingredient is required. The prediction must also exhibit a certain kind of surprisingness.

Suppose I believe fairies cause trees to grow more quickly during the summer months. From this theory we can derive the fairly clear and precise prediction that this copse of trees will grow more during the summer months. The prediction, it turns out, is true. Does that strongly confirm my theory that fairies cause trees to grow more in the summer months? Clearly not. For, though it is true that my theory predicts just such a growth pattern, that pattern is to be expected anyway, even on more orthodox scientific theories about why trees grow.

Similarly, from Dave’s theory that dogs are Venusian spies so ingenious that their devious activities will remain undetected we can derive the prediction that dogs will be observed to behave like harmless pets. This prediction is true. But of course, while consistent with Dave’s theory, the observed behaviour of dogs in no way confirms his theory, as this is just the sort of behaviour we’d expect from dogs anyway, even if they are harmless pets.

The moral is: if the prediction derived from a theory is of something that would not be particularly unexpected anyway, even on rival theories, then the fact that the prediction is true does not strongly confirm the theory. For strong confirmation, the prediction must be surprising in this sense: that, if the theory were not true, then what is predicted would not be particularly expected.

Putting these various points together, we can sum up by saying that, in order for a theory to be strongly confirmed, that theory has to stick it’s neck out with respect to the evidence. It has to be bold, to risk being proved wrong. If a theory either fails to make any predictions, or makes only vague and woolly predictions, or else predicts things that are not particularly unexpected anyway – if, in short, it takes no significant risks with the evidence – then not only is it not strongly confirmed, it can’t be.

Let’s now consider whether Young Earth Creationism and the theory of evolution are, or might be, strongly confirmed by empirical evidence.

Strong confirmation by the fossil record?

We have seen that Young Earth Creationism can be endlessly adjusted so that it continues to “fit” whatever happens to be dug up. Does that mean that it is strongly confirmed by the fossil record?

No. For Young Earth Creationists don’t predict very much at all about what fossils, if any, will be dug up. If we find no fossils, they will say, “Hey, this fits my theory – there hasn’t been enough time for fossils to form”. If we find, as we do, fossils of only simple marine creatures in the lower layers and larger mammals in only the top most layers, then Young Earth Creationist say – “Hey, this fits my theory – this is explained by the differential rates at which corpses decompose and sink”, or: “This is explained by the fact that different ecological zones were submerged at different times.” But suppose species had been found fairly randomly through the layers? Then Young Earth Creationists would say, “Hey, this fits my theory! – The Flood drowned these creatures more or less simultaneously.” Young Earth Creationists fail to make any bold predictions regarding the fossil record. They take no real risks with the fossil evidence. But then their theory can’t be strongly confirmed by the fossil evidence.

What about the theory of evolution? Can that be strongly confirmed? Yes. The theory is a theory of common descent. It says that contemporary species evolved from common ancestors in a tree-like manner, with contemporary species at the tips of the branches and the most common ancestor at the base of the trunk. If the theory is true, the sedimentary layers should reveal fossils arranged in a very specific order, consistent with such a tree-like structure.

In its fully-developed form, the theory of evolution also says that birds and mammals developed fairly late on in the history of life, after the Devonian period. So the theory predicts that not even one fossil of a bird or mammal will ever show up in the lower pre-Devonian deposits (which constitute over half the history of multicellular organisms). As one scientist puts it:

Even one incontrovertible find of any pre-Devonian mammal [or] bird … would shatter the theory of common descent.

These are both clear and precise predictions. They are also surprising predictions, in the sense that, were the theory of evolution not true, and, say, the Flood theory were true instead, there would be no particular reason not to expect, among the countless thousands of fossils dug up each year, at least one or two avian or mammalian fossils in the pre-Devonian layers (Young Earth Creationists would not be remotely surprised if they did). Nor would there be any reason to expect fossils to line up in precisely the way predicted by the theory of common descent. Indeed, that the fossils should happen to line up precisely that way would be a gob-smacking coincidence if the theory weren’t true.

So, in predicting no such fossils will be found, the theory of evolution takes a very significant risk. Which is why the fact that no such fossil has ever shown up very strongly confirms the theory of evolution. (And of course, this is just one example of how the theory of evolution is strongly confirmed. There are numerous others ).

Falsification

We have seen that Young Earth Creationism is not strongly confirmed by the fossil record. The theory of evolution, by contrast, is. Let’s now turn from the notion of confirmation to that of falsification. What of the claim that Young Earth Creationism is not falsified by the fossil record?

A pivotal figure, so far as the notion of falsification is concerned, is the philosopher Karl Popper. Popper developed a philosophical theory of how science progresses called falsificationism. Few philosophers now embrace falsificationism, and I certainly won’t be relying on that theory here. Nevertheless, Popper did make a number of incisive points about falsifiability that are relevant to our discussion.

We have already seen how scientific theories can be falsified – we can derive from them observational predictions that can be checked. If the prediction turns out to be false, then the theory is falsified. However, Popper notes that various strategies can be employed by defenders of a theory to deal with an apparent falsification – to protect or immunize it against falsification.

For example, we have already seen that, in order to derive a prediction from a theory, it’s often necessary to employ auxiliary hypothesis. We saw that Newton’s theory of universal gravitation predicts a smooth elliptical orbit for Uranus only if no other planet is exerting a gravitational effect on it. When Uranus turned out not to have a smooth elliptical orbit – it wobbles slightly in and out of its predicted orbit – defenders of Newton’s theory insisted that, rather than falsifying Newton’s theory, this observation revealed only that there was another as yet unknown object in the vicinity of Uranus tugging it out of its elliptical orbit. In other words, the falsification was deflected away from the core theory and onto an auxiliary hypothesis. Scientists calculated where this mystery object would have to be in order to exert such a pull, looked for it, and discovered a new planet: Neptune.

Here’s an other example. When Galileo constructed his telescope, looked at the Moon, and observed mountains and valleys, it seemed that Aristotle’s theory that every heavenly body is perfectly spherical had been falsified. Instead of accepting this, some defenders of Aristotle’s view suggested that there must be an invisible substance covering the surface of the Moon, filling up its valleys right to the tops of the mountains, so that the Moon is, after all, perfectly spherical. The falsification was in this case deflected away from Aristotle’s theory and on to the auxiliary hypothesis that any material making up the surface of the Moon must be visible.

Other strategies for defending a theory include exploiting vagueness and ambiguity in the theory or the predictions derived from it - to reinterpret them so that what is observed turns out to “fit” the prediction after all. This is, as already noted, a favourite trick of psychics and soothsayers.

Ad hoc manoeuvres

Popper realized that even mainstream scientists can and do employ such strategies in order to defend their theories. He did not think this was always a bad thing. In particular, Popper thought that defending Newton’s theory of universal gravitation by postulating a mystery planet was entirely acceptable, because it led to new tests – scientists could actually look and see if there was planet in the place predicted.

What Popper considered particularly suspect were attempts to defend a theory by means of modifications that introduced no new tests. So, for example, the postulation of an invisible substance on the surface of Moon in order to salvage the Aristotelean theory that all heavenly bodies are perfectly spherical led to no new tests – there was nothing scientists could do at the time to check whether any such substance was there. Popper calls such untestable hypotheses introduced to immunize a theory against falsification “ad hoc”.

Popper noted that the more such strategies are employed to protect a theory from falsification, the less falsifiable it becomes, until eventually we end up with a theory that is not falsifiable at all. In Popper’s view, an unfalsifiable theory is not scientific. Theories that claim to be scientific, but fail to meet the test of falsifiability, are mere pseudo-science.

Two kinds of immunity to falsification


As you have probably guessed, I’m going to suggest that Young Earth Creationism is also an unfalsifiable theory. But, before we look again at Young Earth Creationism, it’s worth taking a short detour to look at two quite different ways in which theories can achieve unfalsifiability. We’ll see that, interestingly, there are two versions of Young Earth Creationism, that each achieves unfalsifiability in one of these two different ways.

Popper distinguishes two ways in which a theory might be rendered unfalsifiable. Indeed, he considered both Marx’s theory of history and the psychoanalytic theories of Freud and Adler unfalsifiable, but for different reasons.

The problem with Freud and Adler’s psychoanalytic theories, thought Popper, is that, whatever human behaviour is observed, it can always be interpreted to “fit” either theory. Popper, who knew Adler, remarks:

As for Adler, I was much impressed by a personal experience. Once, in 1919, I reported to him a case which to me did not seem particularly Adlerian, but which he found no difficulty in analyzing in terms of his theory of inferiority feelings, although he had not even seen the child.

The same, Popper believed, was true of Freud’s theories. They both appeared to fit the evidence, and thus be supported by the evidence, no matter what evidence might show up. Popper illustrated by considering two hypothetical situations – one in which a man pushes a child into water with the intention of drowning it, and one in which a man sacrifices himself to save a child. Popper claims each of these two events can be explained with equal ease in Freudian and Adlerian terms:

According to Freud the first man suffered from repression (say, of some component of his Oedipus complex), while the second man had achieved sublimation. According to Adler the first man suffered from feelings of inferiority (producing perhaps the need to prove to himself that he dared to commit some crime), and so did the second man (whose need was to prove to himself that he dared to rescue the child).

Popper found he couldn’t think of any human behaviour that wouldn’t fit either theory.

It was precisely this fact—that they always fitted, that they were always confirmed—which in the eyes of their admirers constituted the strongest argument in favor of these theories. It began to dawn on me that this apparent strength was in fact their weakness.

So Popper thought both psycho-analytic theories were unfalsifiable, and for much the same reason. Popper also thought that the Marxist theory of history was also unfalsifiable. But for a different reason. According to Popper, unlike Freud’s and Adler’s theories, Marx’s theory started out as a falsifiable theory. In fact, it made some rather risky predictions about how history would unfold. For example, it predicted the character of a coming social revolution (e.g. it predicted a revolution would happen in an industrially advanced society such as Britain). However, this prediction turned out to be largely incorrect (there was a revolution, but not in the way Marx predicted - e.g. it actually happened in industrially backward Russia). Marx’s theory was therefore falsified. Rather than accept this, Marx’s followers employed an immunizing strategy, re-interpreting theory and evidence so that the theory continued to fit the evidence after all.

…instead of accepting the refutations the followers of Marx re-interpreted both the theory and the evidence in order to make them agree. In this way they rescued the theory from refutation; but they did so at the price of adopting a device which made it irrefutable… [by] this stratagem they destroyed its much advertised claim to scientific status.

Whether or not we accept Popper’s claim that an unfalsifiable theory isn’t a scientific theory at all, Popper is surely correct that unfalsifiability is not a virtue in a theory, but a vice.

Dave’s immunizing strategy

Let’s now return to Dave’s theory that dogs are spies from the planet Venus. Mary and Pete tried to falsify Dave’s theory, but each time they try, Pete comes up with yet another explanation for why his theory is, after all, consistent with the evidence. While some of Dave’s moves are rather ad hoc in nature, others are not. His suggestion that the dog’s transmitters were located in their brains did lead to a new test – we could look inside dogs’ brains to check whether any transmitters are there. However, when no transmitters show up, Dave just makes another adjustment – he says the transmitters must be made of organic material indistinguishable from brain stuff. So while not every immunizing move Dave makes is ad hoc, his overall strategy renders his theory unfalsifiable.

In fact, Dave’s theory suffers from much the same problem that Popper found with Marxism. Dave’s theory starts off as potentially falsifiable. However, once it is falsified, Dave develops an immunizing strategy that makes it unfalsifiable. Then, e time his theory runs into trouble with the evidence, Dave just makes another modification to deal with it.

The kind of Young Earth Creationism outlined above is also unfalsifiable, and for much the same reason. The theory that the Earth was created just as described in Genesis starts out as a falsifiable theory. Indeed, it is straightforwardly falsified by a mountain of evidence. In response to the evidence, proponents of Young Earth Creationism, like Dave, then devise ever more ingenious moves to account for it. Once they have embarked on this strategy, their theory becomes unfalsifiable. It’s the strategy developed to defend the core theory, rather than anything about the theory itself, that makes it unfalsifiable.

Gosse’s omphalos hypothesis


There is a contrast to be drawn here with a rather different version of Young Earth Creationism, that developed by Philip Henry Gosse. In 1857, Gosse published a book titled Omphalos: An Attempt to Untie the Geological Knot. Within it, Gosse tried to explain how the discoveries then being made in geology – such as the fossil record – that were beginning seriously to challenge the view that the Earth was just a few thousand years old, were in fact entirely compatible with Young Earth Creationism after all. “Omphalos” means navel, or belly-button. Some Christians wondered whether Adam had one. One the one hand, it seems he wouldn’t, because Adam had no mother to whom he was attached by umbilical cord. On the other hand, it would be seem odd if Adam didn’t have one, as it’s an otherwise universal feature of human beings.

Gosse thought Adam had belly-button, despite that fact that a belly-button might seem to suggest Adam had a mother. Gosse took a similar view about the trees in the garden of Eden, which he thought would have tree rings that might seem to suggest greater age. Gosse then extended this line of thought to the Earth itself. The sedimentary layers strewn with fossils were created by God just a few thousand years ago. Like Adam’s navel, they were put there, not to deceive or to test our religious faith (as some have suggested), but because such creations will inevitably bear the hallmarks of a non-existent past. “It may be objected” Gosse wrote,

that to assume the world to have been created with fossil skeletons in its crust – skeletons of animals that never really existed – is to charge the Creator with forming objects whose sole purpose was to deceive us. The reply is obvious. Were the concentric timber-rings of a created tree formed merely to deceive? Were the growth lines of a created shell intended to deceive? Was the navel of the created Man intended to deceive him into the persuasion that he had a parent?

Gosse concluded that the evidence provided by geology and other sciences failed to settle the age of the Earth: whether or not the Biblical account was true, the Earth would look just as it does.

A striking feature of Gosse’s version of Young Earth Creationism is that, unlike the contemporary version we have been examining, Gosse’s version is immune to refutation by geological and other natural sciences right from the start. It is, in this respect, much like Bertrand Russell’s famous hypothesis that the entire universe, with us in it, was created by God just five minutes ago, though with the appearance of a much longer past (including, of course, our own false memories of that non-existent past past). Both versions of creationism achieve consistency with the evidence. But they achieve it in different ways. Gosse’s version does so by virtue of its content. The currently dominant version, by contrast, achieves unfalsifiability through the use of immunizing strategies.

Biases and presuppositions

Let’s now nail the fundamental myth that lies at the heart of the modern Young Earth Creationist movement. Young Earth Creationists will often cheerily admit that they endlessly adjust and develop their core theory that the Biblical account of creation is literally correct to make it “fit” the evidence. But they typically deny that this entails that their account is not at least as well confirmed as the standard scientific account. Why? Because they think that those who believe in the theory of evolution and a billions-of-years-old universe are doing the same thing.

As this minister of a Creationist organization here explains, both the Bible-literalists and the evolutionists are doing no more than responding to the biases or presuppositions with which they start:

There were a lot of influences in Darwin’s background which would lead him almost inevitably to the point he reached. His father was clearly an atheist. And certainly there was a background of disbelief in the Bible. And certainly there was a belief about millions of years that existed before him. He started his theories from that point. Now I have a clear bias. The Bible. And I admit that. But most scientists do not want to admit these kinds of biases that they have themselves.

Young Earth Creationists accuse the contemporary scientific orthodoxy of having its own bias – towards evolution in particular. Orthodox scientists are doing no more than taking whatever evidence shows up and making it fit their prior commitments. So they are, in this respect, really behaving no differently than Young Earth Creationists.

The Young Earth Creationist Ken Ham concurs:

Increasing numbers of scientists are realizing that when you take the Bible as your basis and build your models of science and history upon it, all the evidence from the living animals and plants, the fossils, and the cultures fits. This confirms that the Bible really is the Word of God and can be trusted totally.

According to Ham, Young Earth Creationists and evolutionists do the same thing: they take the evidence, and then look for ways to make it fit the axioms of the framework theory to which they have already committed themselves:

Evolutionists have their own framework …into which they try to fit the data.

It should now be clear why Ham is misrepresenting what real scientists do. Science is not essentially about achieving fit between theory and data. As we have seen, any theory, no matter how nuts, can achieve that kind of fit, including Dave’s ludicrous theory that dogs are Venusian spies. What a scientific theory requires if it is to be credible is not merely consistency with the evidence, but confirmation by the evidence - the stronger the confirmation, the better. That is why real scientists prefer bold predictions. They take risks with the evidence wherever they can.

As a result of taking such risks, scientific theories can be, and often are, falsified. Even theories towards which scientists are initially very strongly biased can be, and have been, shown to be wrong. Sometimes the theoretical framework with which scientists begin is shown to be mistaken, resulting in a major scientific revolution.

However, because real scientists are prepared to take such risks, their theories can be, and sometimes are, strongly confirmed. Today’s Young Earth Creationists avoid such risks. Like Dave, they have adopted an immunizing strategy such that, no matter what’s discovered, it’s never going to be allowed to falsify their framework theory. One way or another, the evidence will be shown to “fit”. But then, because Young Earth Creationists take no such risks, their theory can never be strongly confirmed.

That Young Earth Creationists take no risks with the evidence is nicely illustrated by the following quote from proponent Bodie Hodge’s “Why Don’t We Find Human and Dinosaur Fossils Together?”:

If human and dinosaur bones are ever found in the same layers, it would be a fascinating find... Those who hold a biblical view of history wouldn’t be surprised… Evolutionists, on the other hand… would have a real challenge. In the old-earth view, man isn’t supposed to be the same age as dinosaurs…. As biblical creationists, we don’t require that human and dinosaur fossils be found in the same layers. Whether they are found or not, does not affect the biblical view of history.

Hodge makes no risky predictions regarding the fossil record. Whatever shows up will be consistent with his theory. Dinosaurs and humans discovered in different layers – fine. Dinosaurs and humans in the same layers – no problem. Hodge is quite explicit that neither discovery would constitute a “surprise”.

What Hodge fails to realize is that it is, precisely, the Bible literalist’s lack of commitment about how human, dinosaur and other fossils should be found that gives the theory of evolution a huge advantage over their own. The bottom line is this: because the theory of evolution takes a significant risk with that evidence, it can be confirmed by it; because Young Earth Creationism doesn’t, it can’t. Young Earth Creationism is no more “confirmed” than is the Dave’s theory that dogs are spies from the planet Venus.

The Blunderbuss

The strategy of making your theory “fit” the evidence and then claiming it is not, after all, falsified, (and is perhaps even confirmed) is often accompanied by another argumentative strategy which I call The Blunderbuss (n.b. a blunderbuss is a sort of early shotgun that flares out at the muzzle). The strategy is this: at the same time as you are employing “But It Fits!” to render your own theory consistent with the evidence, fire off endless salvos of bullshit at your opponents’s theory. Your salvos will comprise (i) a few real but largely irrelevant problems, and (ii) various invented problems.

Of course almost every theory, no matter how well-confirmed, faces puzzles and problem cases. This is certainly true of the theory that life on this planet is a product of natural mechanisms. There remain unanswered questions. Currently, orthodox science is not able to explain how life initially emerged on this planet. Genetic and evolutionary theory can explain how living organisms evolve over time, but it cannot yet fully explain how life initially appeared. Not surprisingly, then, Young Earth Creationists flag up these kinds of question at every available opportunity. The truth, of course, is this: that life has evolved over many millions of years by means of natural selection is nevertheless overwhelming confirmed by the evidence. This genuine and intriguing puzzle for orthodox science does nothing to throw this into question. Nor does it lend the Creationist theory that the entire universe and everything in it was created six thousand years ago any credibility at all. So this “problem” is, in truth, irrelevant to the debate between Young Earth Creationism and orthodox science. The impression that Young Earth Creationists try to create by firing off such “problems” – the impression that their own theory is at least intellectual on par with its orthodox rivals – is entirely misleading.

That was an example of a genuine puzzle that orthodox science cannot currently solve. However, the vast majority of puzzles and problems with which Young Earth Creationists pack their blunderbuss aren’t genuine puzzles and problems at all. More often than not they are invented.

A nice example is polystrate fossils – particularly vertically fossilized tree trunks. Young Earth Creationists will often wow audiences with dramatic images of fossilized trees which can be seen extending upwards through many sedimentary layers. “How can our opponents explain this?” the Young Earth Creationists ask. “According to evolutionists, these sedimentary layers were produced over millions of years, far too long for this tree to have remained without rotting away! Clearly, this tree was buried by these layers of sediment very quickly. That only makes sense on our Flood theory!” One Young Earth Creationist concludes:

Such phenomena clearly violate the idea of a gradually accumulated geologic column since, generally speaking, an evolutionary overview of that column suggests that each stratum (layer) was laid down over thousands (or even millions!) of years.

Except, of course, the “evolutionary overview” suggests no such thing. It allows, indeed it predicts, that trees will sometimes be buried very quickly by a series of sedimentary layers, for example, if located near a river-bank, a volcanic eruption, or area of rapid subsidence. This so-called “problem” for the “evolutionary overview” – which is also supposed to confirm Young Earth Creationism – is pure bunkum.

Sometimes the so-called “problems” for the theory of evolution are quite literally fabricated. Attend a Young Earth Creationist event and you may well be presented with photographs of of dinosaur and human footprints in the same sedmintary layer. The tracks are right there in a rock bed at Paluxy River – “proof” that man and the dinosaurs walked the Earth at the same time! What those peddling these photographs don’t usually mention is that the grand-daughter of George Adams, the man who originally discovered the prints, admits her grandfather carved the human prints by hand to make money.

Young Earth Creationists have amassed a vast arsenal of irrelevant or invented problems to fire off at their opponents in debate. It usually takes time and patience to deal properly with just one example. Often it also takes specialist knowledge, knowledge that scientists specializing in another field may not possess. So it’s often quite easy for Young Earth Creationists to get their opponents bogged down, seemingly stymied by the “problems” they have raised. “Explain this! And this! And this!” they say, and watch with mounting satisfaction as looks of confusion and desperation begin to creep across their opponents’ faces.

As a result, Young Earth Creationists are able to generate the illusion that not only are they able to make their theory “fit” the evidence, their opponents face all sorts of devastating objections. The audience to such a debate many depart misled into thinking that, whether or not Young Earth Creationism is true, there at least remains a live, on-going scientific debate.

Young Earth Creationism in schools


Young Earth Creationism has been, and continues to be, taught in schools. Often, this teaching is done covertly (I know of two British schools where it has been taught by science a teacher without the knowledge or permission of the school or other members of staff – one was one of Britain’s leading independent schools). Obviously I object to Young Earth Creationism being taught as a rival to orthodox scientific theories. People often object to the teaching of Young Earth Creationism on the grounds that children should not be taught things that are known to be false. But that is not my main objection (though teaching known falsehoods is bad enough). My main objection is this: teaching children Young Earth Creationism is scientifically respectable involves teaching children to think like Dave.

The Vision Thing

So effective can “But It Fits!” be in generating the illusion that a theory is overwhelmingly confirmed by the evidence that its defenders may come to think its truth is just obvious for anyone with eyes to see. This may in turn lead them to suspect that those who can’t see its manifest truth must be suffering from something like a perceptual defect. We might call reaching this advanced stage achieving The Vision Thing.

Popper noted something like this effect in some followers of Marx, Freud and Adler. He says:

I found that those of my friends who were admirers of Marx, Freud, and Adler, were impressed by a number of points common to these theories, and especially by their apparent explanatory power. These theories appear to be able to explain practically everything that happened within the fields to which they referred. The study of any of them seemed to have the effect of an intellectual conversion or revelation, open your eyes to a new truth hidden from those not yet initiated. Once your eyes were thus opened you saw confirmed instances everywhere: the world was full of verifications of the theory. Whatever happened always confirmed it. Thus its truth appeared manifest; and unbelievers were clearly people who did not want to see the manifest truth; who refuse to see it, either because it was against their class interest, or because of their repressions which were still "un-analyzed" and crying aloud for treatment.

Young Earth Creationist Ken Ham similarly puts down the inability of his opponents to “see” the manifest truth of creation to their arrogant and egotistical ways:

Why can’t the humanists, the evolutionists, see that all the evidence supports exactly what the Bible says? It is because they do not want to see it. It is not because the evidence is not there. They refuse to allow the evidence to be correctly interpreted in the light of biblical teaching.


Evolutionists deliberately choose not to see what’s right there in front of their noses. Clearly, Ken Ham has achieved The Vision Thing.

Young Earth Creationism, as defended and promoted by people like Ken Ham, is a very impressive Intellectual Black Hole. Indeed, Ham is one of the great contemporary masters of the “But It Fits!” strategy. However, “But It Fits!” is by no means restricted to Young Earth Creationism and fruitcakes like Dave. It crops up in all sorts of places. See the conclusion for more examples.

13 comments:

Mike D said...

Dammit, now you've convinced my broke ass to buy your book. Good thing it's the holidays... maybe I can finagle it as a gift!

In all seriousness, I really can't think of anything to add that suits this post more than an enthusiastic "Yes!" Thank you.

Mike D said...

Wait! I thought of something. I often hear this sort of rationalization with regard to arguments about design and morality. A Christian who used to troll my blog would make statements like, "The order of physical laws in the universe comports with the idea that they were created by an intelligent being," or, "The fact that we seem to place intrinsic value on human life is consistent with the idea that we are created in the image of a loving God." I found such statements asinine, yet difficult to respond to concisely.

Stephen Law said...

Thanks Mike. Actually I think "But it Fits!" is one of the great theistic strategies more generally. For example, it is, in effect, the strategy many use to deal with the problem of evil. Randal Rauser seems to rely pretty heavily on it, it seems to me. So does Alister McGrath. I'm planning to write something about that at some point, when I get a free bit of time.

ashleyhr said...

Stephen

I've just sent the following message to US Christian blogger Joel Watts and two (non-Christian) members of the British Centre for Science Education:

"This is a very interesting read (if one is prepared to pardon his 'french' in his book title):
http://stephenlaw.blogspot.com/2011/12/believing-bullshit-chpt-2.html

For instance he says: "However, because real scientists are prepared to take such risks, their theories can be, and sometimes are, strongly confirmed. Today’s Young Earth Creationists avoid such risks. Like Dave, they have adopted an immunizing strategy such that, no matter what’s discovered, it’s never going to be allowed to falsify their framework theory. One way or another, the evidence will be shown to “fit”. But then, because Young Earth Creationists take no such risks, their theory can never be strongly confirmed".

I tend to agree. I've also noticed the number of times YECs state "this fits with a Biblical model" or "this fits with a creationist model" or "this fits with a young Earth model". Little is said about what the model is and, more crucially, they often fail to examine whether it fits with mainstream scientific models also - and perhaps much better.

After Stephen was criticised at the Answers in Genesis website (for suggesting on UK TV that creationism could trigger a form of 'mental illness'), the responses to his '4 Thought' 90 second talk and his blog of yesterday have been discussed here: http://forums.bcseweb.org.uk/viewtopic.php?f=1&t=2810&start=150 and here: http://forums.bcseweb.org.uk/viewtopic.php?f=1&t=2820&start=195

My recent 'challenge' about falsifiability, which I emailed to assorted YECs on 18.11.11, was made BEFORE I heard Laura Horner make a similar point in her '4Thought'.

I cannot see an email for Stephen Law on his website, so I will try to post the contents of this message under his 5.12.11 blog.

AHR"

Stephen Law said...

Hi thanks for the update. btw I don't say creationism can trigger, or is a form of, mental illness. I say the patterns of thought creationists exhibit would, under other circumstances, rightly lead us to suspect a form of mental illness.

Edward Ockham said...

That was a useful summary of the simple and available evidence for evolution (if you follow my blog, I lay great emphasis on simple and preferably easily observable reasons why a theory should be true.

But I didn't understand the bit about 'must be surprising', tho' I read it several times.

Nick said...

Doesn't YEC still come down to a fundamental belief that a magic man made everything ?

Science, therefore, becomes a means of explaining what the magic man has made.

On that premise YEC has as much validity (in their eyes at least) as science, hence their attempts to claim equivalency.

There still doesn't seem to be any proof that God exists. Doesn't YEC require, therefore, an acceptance of God's existence first and foremost ?

If they can do that then it might get interesting, otherwise its just the cracked meanderings of the deluded.

Tim said...

Excellent book, Stephen. Finished it a few months back. Gave me excellent ammunition to use during debates with people.

Stephen Law said...

Thanks Tim, glad it was of use.

Montag said...

Thanks for a very interesting article: a compelling battle of the paradigms.

I myself like the Intelligent Design theory, and have taken to praying to the Intelligent Designer, rather than the old sobersides "God" or "Yahweh".
Or, rather, I seek to play them off, one against the other, and that way to gain a bit of divine traction for my own Machiavellian schemes.

GearHedEd said...

Polls fairly consistently indicate that around about 45% of U.S. citizens believe [creationism].

This single bit of information makes me feel ashamed to be a U.S. citizen...

Daniel said...

I wish you debate someone who actually knows and understands YEC and does not rely on a single source for accepting scientific claims of a young earth.

My whole life I have been told the scientific evidence for Old Earth is overwhelming, until it is not:

YOUNGEARTH.COM

Anonymous said...

http://kgov.com/real-science-radio

Real Science Radio - RSR is another interesting source of YEC