rationalskepticism.org

Just A Theory wrote:

asyncritus wrote:The comparison of natural selection and mutations to the running of a genetic algorithm of some kind is pure nonsense.

I wouldn't go so far as 'pure nonsense' but there are some major differences. Let's see where you go with this...

The DNA sequence that codes for a functional protein exhibits the specified complexity necessary for it to code for that protein, and is therefore algorithmically incompressible, and a mathematician would therefore describe it as random.

Oh, you went there

Firstly, the term "specified complexity" is an oxymoron. In terms of information theory (specifically algorithmic information theory), complexity is a measure of the information content of a message and is proportional to the length of the program which would fully describe the message when running on a universal Turing machine. It's not strictly a measure of randomness but thinking along those lines will not lead you far astray.

Now 'specification' refers to reducing uncertainty in the information string. High specificity means that the next bit of the message is predictable from what has gone before whilst low specificity means the opposite. Again, there is a link to randomness but it can be easily seen that 'specification' and 'complexity' are actually almost diametrically opposite in meaning. Therefore the term specified complexity is just word salad.

Second, the translation of DNA into proteins is absolutely not algorithmically incompressible due to redundancy in the third nucleotide of virtually every triplet codon. GCT is functionally the same as GCC, in fact there are 64 possible codons and only 20 amino acids plus 3 stop sequences meaning that there is a large amount of redundancy in the genetic code. It is therefore trivially easy to compress the genetic code by removing some of that redundancy.

Finally, a mathematician would not describe the entire process as random because there are clear predictive elements when viewing protein primary and tertiary structure. It is possible to identify hydrophobic/hydrophilic regions of proteins, active sites, alpha helices and beta pleated sheets, all of which display non-random arrangements of amino acids.

Basically, the only correct words in your sentence above were the prepositiions.

Paul Davies says: 'Can specific randomness be the guaranteed product of a deterministic, mechanical, law-like process like a primordial soup left to the mercy of the familiar laws of physics and chemistry? No it couldn't. No known law of nature could achieve this'.

He also said that: 'We conclude that biologically relevant macromolecules simultaneously possess two vital properties: randomness and extreme specificity. A chaotic process could possibly achieve the former property but would have a negligible probability of achieving the latter'.

Paul Davies - you mean the theistic scientist and poster child of the Templeton Foundation who claims that the immutability of physical laws has a basis in Christian theology. Pardon me whilst I chortle in mirth that you would quote this guy in support of a scientific proposition. In fact, let me give you another quote from the estimable Prof Davies:

I had the advantage of being unencumbered by knowledge. I dropped chemistry at the age of 16, and all I knew about arsenic came from Agatha Christie novels

Clearly this makes the genome an impossible object.

Clearly you (and Paul) are peddling doctrine from an orifice more commonly associated with the elimination of waste.

Should someone produce an algorithm which 'creates life', then the following objections are raised immediately:

1 What was the parallel in the primordial soup for the computer's designer?

2 What was the parallel for the algorithm's writer?

It's very obvious, isn't it, that neither was present in the primordial soup busy trying to produce the first life?

Perhaps not, to the bright sparks assembled here.

And yet abiogenesis induitably occurred...