9 May 2009
ScienceBlogs has just posted what can only be called a rant (go here) against the paper by Robert Marks and me that was the subject of a post here at UD (for the paper, “Life’s Conservation Law,” go here; for the UD post, go here).
According to ScienceBlogs, the paper fails (or as they put it, “it’s stupid”) because
(1) As a search, evolution is a multidimensional search. Most of our intuitions about search landscapes is based on two or three dimensions. But evolution as a landscape has hundreds or thousands of dimensions; our intuitions don’t work.
(2) Evolution is a dynamic landscape – that is, a landscape that changes in response to the progress of the search. Pretty much every argument that Dembski makes can be thrown out on the basis of this one fact: all of his arguments are based on static landscapes. Once the landscape can change, every single one of his arguments become invalid – none of them work in dynamic landscapes.
(3) As a search, evolution doesn’t have to work on all possible landscapes. It doesn’t even need to work on most landscapes. It works on landscapes that have a particular kind of structure. It doesn’t matter whether evolution will work in every possible landscape — just like it doesn’t matter that fraction notation doesn’t work for every possible real number. What matters is whether it works in the particular kind of landscape in which our theory says it works. And on that question, the answer is quite clear: yes, it works.
Regarding (1), the work by Robert Marks and me typically focuses on compact metric spaces, which can include infinite dimensional spaces; for the purposes of this paper, which simplifies some of our previous work, we went with finite spaces. But even these can approximate any dimensionality we like for empirical investigations. Regarding (2), we explicitly point out that our approach is general enough to model time-dependent fitness functions (see section 8 — hey, why bother reading a paper if you know it’s wrong and can simply intuit the mistakes the authors must make). What ScienceBlogs appears not to appreciate or understand is that time-dependent fitness functions can be modeled by time-independent fitness functions (”static landscapes”) provided that one represents the search space with sufficiently many dimensions (by going to a Cartesian product — we point this out explicitly in our paper). Regarding (3), our point is that precisely because evolution works with constrained landscapes, those constraints require prior information. Yes, the environment is pumping in information; so where did that information come from? ScienceBlogs resents the very question. But what’s the alternative? Simply to say, “Oh, it’s just there.” The Law of Conservation of Information, despite ScienceBlog’s caricatures, provides cogent grounds for thinking that the information had to come from somewhere, i.e., from an information source.