What’s wrong with Young Earth Creationism? (part 3 of 3) The strange case of the car-stealing elves.

December 5, 2014

In the first two of these three posts on Young Earth Creationism I looked at how Young Earth Creationists are able to make their theory ‘fit’ the evidence, and how they suppose this ‘fit’ reveals their theory is confirmed – as well confirmed as the theory of evolution, say. We saw that for a theory to be strongly confirmed more is required than that sort of ’fit’, which even ludicrous theories can achieve.

 

But what more is required? When is a theory strongly confirmed by the evidence?

 

Consider this general rule of thumb: a theory is confirmed by a piece of evidence just in case the evidence is much more probable given the theory than it would be otherwise.

 

According to this rule, when considering whether a theory is confirmed by the evidence, you should consider how probable the evidence is given that theory.

 

Here’s an example. Suppose I see water droplets on the window and you come in wearing a wet shoes. Intuitively, that’s fairly good evidence it is raining. Why?

 

Part of the reason is that, if it were raining (my theory), those water droplets and wet shoes (the evidence) are just what I’d expect to see. If it’s raining, the probability I’d observe these things is high.

 

However, our rule of thumb says this isn’t the only probability we need to consider. For my theory to be confirmed, the evidence should also be rather less probable if the theory weren’t true.

 

To see why this second probability does seem to matter, let’s change my original example a bit. Suppose I know my neighbour has a powerful garden sprinkler that they use daily at around this time. It’s so powerful it sprays my windows and garden path. Given this background knowledge, the water on the window and your wet shoes are now much less good evidence it’s raining. For that’s the sort of thing I’d expect to observe even if it weren’t raining.

 

So it seems that the difference between these probabilities is important: the probability of the evidence if the theory were true, and also the probability of the evidence if the theory weren’t true. If the former probability is higher than the latter, then our theory may be significantly confirmed.

 

Notice both probabilities can be low and yet still the theory may be strongly confirmed if one probability is nevertheless much higher than the other. Here’s an example involving the theory of evolution. Every now and then a whale crops up with atavistic limbs – legs. Fish never display such limbs. This is considered powerful evidence for the theory that whales evolved from earlier land-dwelling mammals. Why so? Not because atavistic limbs are highly probable given that evolutionary theory. Perhaps the probability of such limbs showing up is fairly low even on that theory (maybe we would not predict atavistic limbs given the theory, say). But still, even if the probability of atavistic limbs is fairly low on that evolutionary theory, it’s still many, many times higher than on the view that whales did not evolve in that way. So those atavistic limbs do still strongly confirm that evolutionary theory about whales.

 

What about the fossil record? Why does that confirm evolutionary theory? As we dig down through the sedimentary layers, we find different species fossilized in a very specific order. For example we find only simple life forms in the lower layers, with higher layers revealing new species that appear as modifications of those below them. The fossil record reveals a tree-like structure of species emergence, with current species tracing back to a common ancestor. We never find fossils inconsistent with this theory: fossil rabbits or birds in those deposits classed as Pre Cambrian, for example (as JBS Haldane famously noted).

 

Now the fossils of different species being arranged through the sedimentary layers in this very specific way is exactly what we would expect on evolutionary theory (assuming we expect there to be any fossils at all). On the other hand, there’s little if any reason to expect this very specific arrangement if Young Earth Creationism is true. Indeed Young Earth Creationists wouldn’t be much surprised if fossil rabbits did start showing up in the Pre Cambrian layers. If the fossils were produced in the way most Young Earth Creationist now suggest – largely by those species being drowned and then buried in mud deposits created in just a few days or week during the flood on which Noah floated his Ark – then their being fossilized in that very specific order would be improbable. Indeed, that ordering would be the most extraordinary cosmic fluke. So, given that sort of arrangement of fossils is very probable on evolutionary theory and highly improbable on the alternative, the arrangement strongly confirms the theory of evolution.

 

So there are a couple of examples of how the theory of evolution is confirmed (by the fossil record and atavistic limbs). But we have barely scratched the surface: the evidence for evolution extends vastly beyond this.

 

Could Young Earth Creationism be strongly confirmed, at least in principle? Yes. If, on excavating the ground beneath our feet, we had discovered, not fossils, but a bottom layer clearly and repeatedly stamped ‘Made by God, 4004 BC’, that would provide a significant bit of evidence for Young Earth Creationism. Combined with other evidence, it might make Young Earth Creationism overwhelmingly confirmed.

 

Still, we've not entirely pinned down the conditions under which a theory is strongly confirmed. What we have said is that, as a rough rule of thumb, a theory is strongly confirmed when the evidence is much more probable given the theory than it is otherwise.

 

But that’s not quite right. Consider this. Anything that seems bafflingly improbable can always be explained by invoking some sort of hidden agent or being with both a desire that that state of affairs should exist and the magical ability to make it so.

 

Why do flowers grow in the Spring? Here’s my theory: Because there exist fairies who love flowers, like to see them bloom in Spring, and have the magical power to make them bloom at that time.

 

Why does the elephant have a long nose? Here’s my theory: Because an irritable nature spirit became annoyed by an elephant one day, and so decided to curse all elephants with a ridiculously long nose.

 

Why isn’t my car where I seem to remember having left it? Here’s my theory: mysterious car elves fell in love with it and moved it magically to their secret lair on Venus.

 

Now if I really can’t otherwise explain why flowers bloom in Spring, why elephants have such a long nose, or why I can’t find my car, should I conclude that these mysterious and magical beings are indeed in each case responsible? Surely not. Yet notice the probability of what is observed really is in each case much higher on the magical being theory than it is otherwise.

 

Clearly, something’s gone wrong here. It can’t be that easy to confirm the existence of fairies, irritable nature spirits and car stealing elves, can it? But what exactly has gone wrong?

 

I’ll leave that for you to think about. Feel free to make suggestions below…

 

Also consider: is there a moral to draw here when it comes to invoking that mysterious and magical being God to explain other things that strike us as bafflingly improbable?

 

Comments:

#1 bhlar on Friday December 05, 2014 at 10:14am

While I agree with the premise, I must take semantic issue with your approach. The notion that one can “confirm” a “theory” is not good science. A theory can be supported by an enormous body of confirmed hypotheses based upon it, but is still subject to rejection as soon as there is evidence against it.

These usages allow science deniers (be it evolution, human influenced global climate change, or anything else) to work their arguments in via lexical gymnastics. In the same way, claiming that something is true siting consensus in a field is opens a door. It is not consensus of the people in a field, but of the tested hypotheses in that field that support or falsify. Breaking consensus of people doesn’t matter, unless there is a new measurement or observation that can back it up.

These issues are obviously semantic in nature, but their abuse is often exactly what traps debates which are otherwise not supported mutually by merits.

#2 wombat (Guest) on Friday December 05, 2014 at 3:38pm

One minor quibble with respect to the commonly held view that increasing complexity of organisms reflects recent development. This is not always the case. Counter examples are provided in Dawkins books and include cases where various faculties and associated body parts have been lost as the species become more adapted to a particular environment. Your article indeed cites the whale having lost its legs and become aquatic but there are some more striking examples particularly in parasitic organisms which have evolved to suit specific hosts and lost a great deal - all limbs, eyes, stomachs and digestive systems.  They are much simpler than their ancestors were but very much more specialised.

YEC proponents should not merely be unsurprised to find bunny bones next to the stegosaurus bones, their theory seems to make a strong prediction that this is what we should find. After all an overwhelming percentage of the population of animals of all species was supposed to have been drowned at the same time. Only two pairs of bunnies were saved.(Genesis 7:2).  According to Ham YEC’s claim that the Ark had a pair of steggies and brontos and all the other ‘sauruses but those obvious extinctions happened afterwards. Apparently due to man’s activities - climate change no less - and that old standby, sin. (see answersingenesis.org )

The point here is that this type of theory often seems to make quite strong predictions (as a logical conclusion of its premises) which are then neglected by the proponents.

#3 Stephen Law on Saturday December 06, 2014 at 2:29am

Thanks wombat - but I didn’t say things can’t get simpler (I am well aware they can), only that they started out simple.

Bhlar - Yours is indeed a semantic disagreement. But you should be aware ‘confirmation’, as used in philosophy of science and confirmation theory, is a matter of degree and can be weak very weak. E.g. observation of a single white swan ‘confirms’ all swans are white. Hence I often felt the need to qualify ‘confirm’ with ‘strongly’ above.

#4 Philip Rand (Guest) on Saturday December 06, 2014 at 4:30am

Funny riddle Dr Law…

What has gone wrong with respect to your elves is that causality cannot be applied to them.

And if causality is excluded then it cannot be described.

Interestingly, all you are doing is replacing one superstition with another to explain the disappearance of your car!

Here is another riddle….

You see a bee flying around in front of you…you grab it with an outstretched hand…

What do you see?

#5 Philip Rand (Guest) on Saturday December 06, 2014 at 5:33am

Of course I could say…

Yes, you are correct elves did steal your car and take it to Venus…BUT…what you really meant when you said “elves” was “wife”...and what you meant when you said “Venus” was “Mother-in-laws house”.

Scientifically, it would be like saying to proponents of phlogiston in the 19th century…yes, chaps phlogiston does exist…it’s just that when you said phlogiston you really meant valence electrons….

However, I am still using causality.

#6 wombat (Guest) on Saturday December 06, 2014 at 11:00am

Well Dr Law of course you are aware of the complexity issue but you did write “For example we find only simple life forms in the lower layers,... “ Which seems to imply that there is at least a very strong tendency to increasing complexity as we ascend the layers.  At the limit I suppose this must be so as we progress from fossil traces of single celled animals (e.g stromatolites) to trilobites but any ordering w.r.t complexity after that seems fraught.

#7 Philip Rand (Guest) on Sunday December 07, 2014 at 1:51am

Hi Mr wombat

In many respects this last part of Dr Law’s thesis is
superfluous.

It is because if you watch the discussion between Dr Law and Richard Dawkins they both agree that Darwin’s Natural Selection model is in fact a piece of armchair logic, i.e. as Dawkins says…Darwin did not have to travel the South Seas on the Beagle to come up with his theory…he could have done it in the comfort of his own home.

This means that Natural Selection is “logical” and is “deterministic” in both Dr Law’s and Richard Dawkins eyes…here they compare the model to the thought experiments Galileo did concerning gravity.

So, to say that Natural Selection is “probably” true is nonsense…it has to be because according to them if we push this advice to its logical extreme, Natural Selection is deterministic and one doesn’t need to use the concept of probability any longer.

I mean, in the end the usefulness of probability stems from the fact that the description of nature becomes simpler by ignoring intentionally some of the less important factors…

But, according to Dr Law and Richard Dawkins one does not have to do this with Evolution…because Evolution is deterministic.

#8 Adrienne (Guest) on Thursday December 18, 2014 at 1:09pm

Going back to the sprinkler vs. rain example, it is more reasonable to assume that your neighbor’s sprinkler caused there to be water droplets on your window only because you already have knowledge of your neighbor’s sprinkler. But if you did not know about your neighbor’s sprinkler, it would not be unreasonable to believe that it had been raining. But in both cases, what makes each explanation reasonable is that you have observed water coming out of a sprinkler or falling to the earth as rain. It is the fact that you have previously observed these occurrences that makes them reasonable explanations. But when it comes to fairies, nature spirits, and car-stealing elves, you have never observed these things in real life, so it is not reasonable to assume that they even exist in the first place, much less that they are responsible for your missing car, etc. So it may be that your car going missing fits perfectly with the theory that mysterious elves stole it. But in that case, the reason that the explanation is unreasonable is not because the evidence (missing car) does not support the theory, but because the theory itself is unreasonable because it is based on something (elves) that has never been observed.

Since all of the examples of elephants having long noses, flowers blooming in spring, and cars going missing have reasonable natural explanations, I think the moral would be to assume that every natural phenomenon has a natural explanation, even if you aren’t sure what it is yet. When most people could not think of a natural explanation for phenomena that we now have natural explanations for, if everyone had been content with supernatural explanations, science would never have progressed.

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