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Bob Murphy invokes my expertise on information theory to criticize (yet) another bizarre argument from Steven Landsburg, that the natural numbers are more complex than human life. Here's the mistaken part of Landsburg's reasoning:
...the most complex thing I’m aware of is the system of natural numbers (0,1,2,3, and all the rest of them) together with the laws of arithmetic ...
If you doubt the complexity of the natural numbers, take note that you can use just a small part of them to encode the entire human genome. That makes the natural numbers more complex than human life. Unless, of course, human beings contain an uncodable essence, like an immortal soul
Naturally, I don't necessarily agree with the broader theological points Bob makes in his reply, and such issues will remain even scarcer on this blog than on his. However, I will expand on point I made in discussion with Bob.
The error in Landsburg's line of reasoning is: the fact that you can use instances of X to build Y does not mean X is more complex than Y. Just the opposite, in fact: in order to describe Y, you must describe X as a substep. Like in the analogy I gave, you can use bricks and mortar to build a house, but that means it's the house that's more complex. To fully specify the house you must describe not only the bricks and mortar, but the form they take as a house -- how they're supposed to be put together.
As for arithmetic and natural numbers, it's their lack of complexity that makes them so useful. By appealing to it, you can make sense of a diverse array of phenomena. The more complex arithmetic were, the less helpful it would be in making sense of things.
Just to be clear, this doesn't mean it's easy to learn math (different people have different problems in different topics and levels), or that you can't do anything complex with math. The point is that no amount of complexity produced in using arithmetic could ever imply arithmetic's complexity, for the same reason that no matter how complex a house you make with one kind of brick, you can't make the brick more complex.
But of course, Landsburg's errors don't end there. He wants to go so far as to say that by merely encoding the genome in base 4, you've described human life. That's certainly the impression people get from discussions of DNA in the popular media and movies like Jurassic Park. Hey, all you need is a string of letters made up of A,G,C,T, and you've described someone completely!
To put it mildly: that's not how it works. First of all, you need to say what the letters actually mean. And then, even if you know that much, all you have are empty labels -- suggestively named LISP tokens. So you know that C is cytosine? Okay, but what's that? Now you need to describe where the carbons and nitrogens and oxygens go to make up cytosine. But wait -- what's this "nitrogen" thing, anyway? And so on.
Don't worry -- the process terminates: once you've described the generative model that puts all of these concepts together in a way that yields a description of human life as its output.
Needless to say, you're using more than a few integers by that point!
