Saturday, May 28, 2011

Signature in the Cell, reviewed by David vun Kannon

I won my copy of Signature in the Cell in an essay contest on the intelligent design advocacy blog, Uncommon Descent. I didn't even pay for shipping.

I made a strong attempt to read it through in order to write a review of the book for UD. Sadly, that blog often bans dissenting voices, so my review will have to be published here instead.

The book is too long for its stated purpose. For its unstated purpose, it is about right. The stated purpose is to review the history of DNA science, and Meyer's own life, as a framework to explain the inadequacy of naturalistic explanations of the genetic code. The unstated purpose is to throw a lot of basic history and science at the reader so that when the science becomes merely 'sciencey' most will not notice the transition. The result is that three small books (DNA for Dummies, My Life, and ID, the Theory That Couldn't) have been woven together and sold as one.

On p. 143, Meyer tells us that "The idea of design helped liberate Western science from such fact-free reasoning." "Such" reasoning belonged to the Greeks that argued from first principles, and purely from logic, to the actual state of the world. Signature in the Cell almost immediately falls back into that error when Meyer argues purely from logic, analogy, and common sense instead of experiment and calculation.

This abandonment of experiment is what most clearly justifies calling the book non-scientific, and even anti-scientific. A good example is Meyer's treatment of Michael Polanyi's arguments on pp 237-243. Meyer is convinced when Polanyi 'argues', 'insists', and 'concludes' all without doing a single experiment. It is the logical structure that is convincing. This is a retreat from science.

Polanyi's argument is central to many claims of ID, so lets talk about it a bit deeper. Polanyi makes the claim that to function as a code, the order of the bases can't be forced by potential energy. ATC and G must be free to come in any order. This is argued by analogy to human communication systems.

However, we already know there are exceptions to such rules. In English, Q must be followed by U. And yet, we somehow stumble forward using English to communicate. Similarly, there may be slight influences in base to base sequence.

Polanyi was writing when almost nothing had been sequenced, today we have thousands of complete genomes to test the idea. But testing the idea is irrelevant if Meyer is already convinced by the logic.

Since Meyer is focused on the genetic code, Polanyi's argument is a major intellectual roadblock. Sequence independence of symbols is far less important than the translation from one symbol system to another, in understanding what a code is and how it functions. DNA is a code for protein (and RNA). Sequence independence means random sequences can acquire meaning slowly and stochastically, not that the entire code was graven on tablets of stone before the world's creation, and then delivered from heaven by a choir of angels.

This process of "acquiring meaning" in the case of the genetic code means narrowing down the association of each triplet of bases from any random amino acid to a specific amino acid. There is a lot of evidence that this process is at least in part driven by the laws of physics and chemistry, contra Polanyi's pronouncements of 40 years ago. But you are not going to learn that from Signature in the Cell.

Meyer also indulges in a 'big number' argument about the size of proteins (and RNA polymers). Starting from an assertion that we need 150 amino acids for functionality, and old and often refuted argument follows that the universe doesn't have the resources to find even one such protein. Sadly no. Meyer ignores all evidence that vastly smaller fragments of protein have useful function.

Function in proteins is often associated not with a specific arrangement of amino acids, but with the polar/non-polar nature of the amino acid. (If you want to think in terms of symbols, this is cutting down the number of symbols from 22 to 2.) While the universe can't explore 22^150 sequences, it certainly can explore 2^15 sequences, then use two of the best 15-length sequences together in a 30-length sequence. Etc, Etc. But Stephen Meyer is not going to tell you that.

Signature in the Cell is padded with a lot of historical information. Dr Meyer can claim that it is included to show that he is giving every argument a fair opportunity. Exactly the opposite is true. In chapter 14, pp 296-297, Meyer recounts an exchange with Dr Kenneth Miller over his coverage of the RNA world in an article from 2000.

The article, DNA and Other Designs, is still available on the Discovery Institute web site. I recommend reading it, since it says just about everything that Meyer says in this large book, and for free. But just as Signature in the Cell recapitulates and expands on that article, it recapitulates the error of that article as well. As Dr Miller complained in 2000, Stephen Meyer lies by omission by "not having the space" to mention 20 years worth of research in the RNA World hypothesis. Now it is 28 years, and the page count of Signature in the Cell spent on long forgotten theories crowds out discussion of current theories and work that directly undercuts the main ideas of the book.

There is no mention of the work of Michael Yarus' lab, no mention of the stereochemical hypothesis in the origin of the genetic code. This is the key work that Meyer has to come to grips with if his whole facade of looking into every possibility is to have any credibility at all.

It might be an acceptible debating technique to dodge your opponents best arguments until the time runs out, but that kind of rope-a-dope argumentation isn't science. That is the bottom line verdict on this book. It is not looking at everything and arguing to the best explanation. It is picking and choosing, retelling lots of old stories, personal stories, and some basic science, while avoiding the experiments and evidence that would challenge ID, and collapse its claim to be the best explanation of anything in the universe larger than Stephen Meyer's paycheck. ID explains that perfectly well.

No comments: