Monday, March 01, 2010

Explaining Fantasy

I've been busy with meatspace lately, so I don't remember if I've said something about this before, but I figure it's worth drilling home. In science, most people understandably focus on how theories are supposed to predict and explain the facts that we observe. I, however, feel the need to point out the opposite side of that: A theory also needs to explain why certain things are not seen. It's been said that "a theory that can explain anything explains nothing," and it's my intention to give the reason for that saying.

Let's use the familiar comparison between evolution and Creationism. Evolution has constraints: A generation can only build on or modify what it inherited from its ancestors. Evolution tells us that Crocoducks are absurdly unlikely: Birds evolved from bipedal dinosaurs, a different branch of the tree of life from crocodiles. A Crocoduck would be analogous to (but much more extreme than) a couple siring a distant cousin's child. For that reason, the discovery of a Crocoduck (barring origin by mad science) would completely dismantle everything we know about genetics and evolution.

Creationism, however, can perfectly explain a Crocoduck: God can do whatever he wants, and for some incomprehensible reason was in the mood to slap two very different species together. There is no mechanism of action to limit what God's tools can do. Thus the Crocoduck is explained by Creationism.

Of course, the problem this presents for Creationism is that there are no Crocoducks. There are no lion-eagle hybrids with a six limb body plan. There are no cloven-hooved horses with spiral horns or lion tails. Creationism is useless because it can be used to predict anything, including all the things that will never happen. Creationists have no method for sorting out true predictions from the infinity of fantasy predictions. They can only point out certain "predictions" after the fact has been observed. That, in a nutshell, is why Creationism's unfalsifiability makes it useless.

Often, I call Creationism "The Random Theory of Randomness." If you think in terms of a dice experiment, I think it's quite apt: If you roll a die a million times and get all sixes, it's perfectly reasonable to think the die is weighted in a manner to come up six. That theory has a comparatively narrow set of predictions: If you keep rolling the die, you will get mostly sixes. The theory of randomness, that the die roll just happened to come up all sixes by chance alone, predicts any outcome pretty much equally.

If you rolled the die some more and get a roughly equal tally of all six numbers, that would cast heavy doubt about the die being weighted. If you continued to roll sixes, it would support the weighting theory, but the randomness advocates could just as readily claim that it's possible random chance still favors sixes. Of course, I would think any reasonable person would bank on the weighting theory.


djfav said...

I hadn't thought of Crocoducks that way before.

Show me the Crocoducks!

Jim Roberts said...

And, please, creationists, don't show up extolling the platypus as an example of a crocoduck. It's NOT a beaver and a duck smushed together. Even a cursory examination of an actual platypus would show you that.

BKsea said...

Thanks for this astute post. I've always found the Creationist argument of "Why are there no crocoducks" to be very ironic. It seems to be a much better argument against creationism than for it. If we accept that there is a Creator, then we can clearly see he freely reuses essentially identical parts across species. But why is this reuse limited to species that are highly similar in many other features? Why recreate a platypus bill from scratch with different materials when you have already created a duck bill? Why aren't there any crocoducks?

Jim Roberts said...

And it's part of the reason why irreducible complexity itself falls apart - even if you can construct an argument that the flagellar motor is irreducibly complex, it's not as though there's one design. There's dozens - hundreds. So, God decided to personally handcraft all these different designs, none of which are especially efficient, metabolically?

Bronze Dog said...

Something to add to BKsea's point: I would think that if Creationism were true and the "common features, common designer" line they tout were also true, the world would be more like one from Spore, where any creature, no matter how distant (in terms of lineage, time, or physical space) could have an identical feature with any other. In Spore, you could easily make a wolf with hooves by borrowing from a completely different creature's DNA.

Evolution can't do that. To get a hooved wolf, they'd have to evolve their own way of growing hooves, and that would result in a new, distinctive method and structure instead of a flat or even modified copy like a designer might be expected to do.

Jim Roberts said...

Heh. Just finished statting out the leucrocotta (canine-like critter with plates instead of teeth and hooved feet) and writing its ecology, which involved some pretty radical evolution.

If the world of life is designedat all, then it isn't by someone reaching into their toolbox and pulling out parts, it's a watchmaker who set the machine in motion and who, I think, is as fascinated by how the cogs have elected to spin as we are.