In a recent post at Uncommon Descent, vjtorley links to this paper by Gregory Chaitin, and a talk by Chaitin:
Anyone have any comments? To me, his paper seems to report a rather strange evolutionary model.
18 thoughts on ““Life as evolving software?” – Chaitin”
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Chaitin is a mathematical logician. He is not a biologist.
I trust what Chaitin has to say about Darwinism as much as I trust what a biologist has to say about Godel’s theorem; that is to say, I do not trust it at all.
Chaitin seems to be modeling combinatorial explosion without any Darwinian filtering. It might make for interesting mathematics, but I don’t see it as having any relevance to Darwinism nor to ID.
Incidently, I download the pdf of that paper several months ago. It’s in my “to read” box, though I am not feeling any urgency about it. I have read some of Chaitin’s earlier work. I have been underwhelmed by it.
I started reading the paper, but my motivation to continue reading suffered a blow when I read this at the start of section 2:
For many years we have been disturbed by the fact that there is no fundamental mathematical theory inspired by Darwin’s theory of evolution
We? Speak for yourself, dude. Could he really be unaware of the mathematics of Ronald Fisher (who derived the Fundamental Theorem of Natural Selection, Sewall Wright, Moto Kimura and many others?
Or is that not “fundamental” enough for him?
Well, the model he describes in his paper doesn’t even seem to be “Darwinian”. He’s got a crude fitness function (his “oracle”) but that only seems to compare parent with offspring and select the best. And he still needs an extra “oracle” to deal with the non-terminating programs. He describes it as a “hill climbing” algorithm, which it is. Which is very limiting.
And yet he still notes that once he gets his mutations right, the system behaves more like intelligent design than like “exhaustive search”!
this is exactly the kind of post and topic that Mark Chu-Carroll (MarkCC) over at Scientopia (now) would be the perfect expert to comment on. (http://scientopia.org/blogs/goodmath/). Despite his distaste for anything at UD, he has occassionally in the past eviscerated a few math-focused or information-focused claims. If anyone here (Dr. Liddle?) has the prestige to catch his attention, it would be awesome to hear from him!
Good thought 🙂 I’ll have a go. He may have written something already.
Liz,
Populations don’t adapt to their environment. Scoprions, turtles, alligators, lizards they’ve been around for more than 300 million years and they haven’t changed. They look basically the same as they did when they were first around. I’ll get a quote form Prothero in a bit.
And you think they aren’t adapted to their environment?
That’s odd 🙂
They all look rather well adapted to me!
Anyway, welcome to TSZ!
Now here’s a simulation that is a little more convincing, I think! And a nice example of adaptation.
I found the comment regarding the size of the human genome and the time needed to get there a bit suspicious.
For one thing nobody thinks that the entire genome was a product of purely Darwinian step-wise selection like the model simulates; there’s a whole raft of concomitant processes at work that would need to be taken account of.
Also nobody believes that each element of the entire genome was selected for. Despite protestations to the contrary the human genome does in fact appear to be overflowing with junk. (The scattered fossils of viral DNA etc). So when Chaitin’s friend informs him there’s not enough time for Darwinian natural selection to arrive at X it appears that the X being modelled bears little resemblance to its real life genomic counterpart.
This assumes I’m understanding Chaitin’s model correctly, obviously.
Elizabeth,
the point is the environment has changed enormously over the last 300 my and yet they still look the same as they did back then. all species are adapted to their environment, otherwise they wouldn’t exist. species don’t change their body plans to fit a new environment. further, a species that has been around for 100 my is just as likely to survive the next mass extinction as a species that has been around for 2my. Species do not develope new adaptations that enable them to improve their odds of survival.
Woodbine,
If the human genome is littered with junk then why is it repetetive [sic]? Repetition is not something chance can produce.
Elizabeth,
The author of that video is assuming that chance and law can build those virtual creatures. You need planning in order to build those creatures. Notice that he starts with creatures already built. He conveniently skips the part about how those virtual beings come to be in the first place. Moreover, he’s assuming that building a virtual organism is way more easy than it really is. The human for instance has 100 trillion cells, divided in 250 cell types, into 22 internal organs, built with a code of 3.2 billion qubits. Those virtual beings, some of whom had just 8 parts or so.
No, he’s not starting with creatures already built, Bob. Check out the interview that is linked in the first few frames. Nor is he assuming it’s “way more easy than it really is”. He’s showing how these functional virtual creatures can evolve to do things simply through evolutionary processes.
Clearly it’s not a simulation of the evolution of human beings! But it is a demonstration of just how powerful and “inventive” evolutionary processes are.
ETA: Thinking about this, I probably misunderstood you. Yes, he does start with minimal “creatures”, but those capabilities like swimming and walking emerge through evolution.
Elizabeth,
you’re just assuming that capabilities emerge through random processes, you have no casual account of how chance and law can bring that about. there are 35 million mutations between the chimp and the human. i’m not suggesting that they don’t share a common ancestor, but i am suggesting that randomness and the law if it does not work then it gets discarded can cause those 35 million mutations to spread through the ENTIRE population. no darwinist has ever given an account of how even ONE of those mutations arose by chance and just happened to give the organism a selection coefficient greater than x. doesn’t that disturb you? why you believe in a theory when no casual account for it has been given?
No, I’m not “assuming it” – that video I posted demonstrates it!
What do you think is doing the “designing” of those swimmers and walkers and followers and catchers?
Sure we do. As long as we start from a basic self-replicator that replicates with heritable variance in reproductive success, variants that reproduce better in the current environment will become more prevalent. And we know a lot about how the genotypic variance is generated, and a lot about how it that translates into variance in reproductive success in the phenotype (better camouflage, for instance, more efficient motility).
Well, you yourself probably have a hundred or so genetic sequences that your parents didn’t have 🙂 How are you estimating that 35 million, btw?
Well, you seem a bit confused about the theory. There are a great many causal explanations as to how new sequences (mutations) are generated. And the novel sequence doesn’t have to give the organism a reproductive advantage at first appearance to have a sporting chance of propagating through the population. What matters is that the population itself has plenty of variance so that when environmental changes occur, it can adapt.
This btw is something that seems to me to be missing from Chaitin’s model.
Neo-Darwinism, as the name itself implies, is not Darwinism—not the theory of evolution Darwin proposed. Skeptics should know. Chaiten is correct. Darwin’s theory of evolution has never been “mathematicized,” and Chaiten doesn’t do it either.
It can’t be done… It’s way to complicated. Life is far too complicated to mathematically describe its exact evolution.
It’s not that Darwin’s theory hasn’t been reduced to math—No theory of biological evolution is so reducible.
Rock wrote:
“It can’t be done… It’s way to complicated. Life is far too complicated to mathematically describe its exact evolution.”
Sure, just like the exact evolution of lots of non-life defies mathematical description. Nevertheless, highly simplified mathematical models of certain aspects of evolution (e.g. On the Origin of Species by Natural and Sexual Selection) can be quite useful in aiding our understanding of evolution. The theory of evolution can be regarded as a collection of mathematical models, with partially overlapping limited domains of applicability.
As the famous mathematical ecologist Richard Levins once said (I paraphrase):
our truth is the intersection of many independent lies
And our lies are the intersection of one truth.