Intelligent design: Beta version.

Biologists must constantly keep in mind that what they see was not designed, but rather evolved. (Francis Crick).

cont. http://shkrobius.livejournal.com/121946.html, http://shkrobius.livejournal.com/136502.html

What little I know about “intelligent design,” I’ve learned from Behe’s popular books. This was disappointing and tedious reading. Most of the arguments were the familiar criticism of evolutionary theories and belaboring the vague notion of irreducible complexity. I’ve seen much better advocacy for both of these. The costructive part was added as an afterthought.

The way I understood Behe’s point is that there is an external intelligent agent in biological evolution that dirties its mighty hands with every little change in the genome, in this fashion providing irreducibly complex biochemical adaptations to a billion of species that populated this planet. The extravagancy of this view is bewildering: the idea that such petty meddling is not the way by which our Maker runs His world goes all the way to Maimonides and beyond. What next? Seraphim steering the planets? Does one design intelligently if one needs constant tweaking of one’s design? What was the point of creating Nature ruled by law and then systematically breaking this law in order to create a bombardier beetle, the blood clotting system of the vertebrates, cilial motors, opsins, an so on? If we discard the insane assumption that such supernatural tinkering is constantly going on, as suggested by everything we know about how Nature works, we still have to explain how does evolutionary innovation occurs. Nobody knows the answer. Answering this question is quite a challenge. However, what Behe argues for is a refusal to look for this answer that is elevated to a principle. This is absurd. Yet these books are not all bad, as these do provoke thought about what “intelligence” and “design” mean. Whatever is Behe’s “intelligence,” it cannot be human intelligence. What do we know about designs that are designed by inhuman intelligence? Should we stop at the living creatures? Are mountains and clouds designed, too? One can find any amount of irreducible complexity in timed dripping of a leaky faucet… And yet, and yet…

You see, Behe is a biochemist, and my heart goes for him, because I know where it comes from. A lot of biochemists think much like Behe, though few would admit that. If you are looking at a working of an enzyme, thinking about it in evolutionary terms seldom gets you anywhere. This is true in general: the most productive way of thinking about biomolecules is treating these as machines that are optimized for their specific tasks. If you imagine what is the best way of doing something under such and such constraints, following certain general guiding principles, you will frequently hit on the same features. I do not want to go into particular examples; rather I’ll provide a sketch of this mode of thinking, for illustration only.

Consider the scenario: we have decided to make Mars habitable for ourselves (in the distant future; we are in no hurry). We need water and oxygen; there is no oxygen and very little water on Mars. Ice can be transported from the Oort cloud (by crashing comets onto Mars surface, by subtle orbital perturbations of the comets), and CO2 too, to make it warmer, but one needs to turn this water into oxygen. To do that we can build a huge solar-powered electrolysis plant. But that is our way of doing things, and we are not too intelligent. The intelligent way of doing this is making a plant that makes itself using the local resources. It should be versatile, adaptible, and autonomous; one of the ideas that comes naturally is having this plant to consist of a myriad of small elements, which we will call cells. It is clear that the machinery has to be complex, as these cells should create themselves and explore and utilize whatever is in the environment. Furthermore, as oxygenation is a billion year project, they should adapt to the changes they themselves exert. So the machine should be based on heritance with variation. Yet it is not this principle (which is but the means) but the task set by the designer that truly matters, and this task is doing chemistry driven by solar energy. Because the task is making molecules, it is best handled on molecular scale. What we need are molecular machines doing the job and also making and repairing themselves. That can be done in a number of ways, but the simplest one is this: let’s have a universal linear polymer on which we’ll place functional groups. We will have acids, bases, electron donors and acceptors, ion binders, hydrophylic and hydrophobic groups – a bit of everything. Since our cells will be in water (making water into oxygen) it is natural to design these machines in the following way: the hydrophylic and hydrophobic groups are placed in such a way that when the polymer is in water it folds itself into a unique complex shape. You need this uniqueness and complexity, because you would have lots of such machines jumbled together, thousands of them. You do not want them to stick to each other, block each other’s reaction centers and recognition sites, etc. You want them to do their job, meaning excellent molecular recognition of their substrate. So we need pliable, complex structures. It is immediately apparent that we also need stereochemical control. It is hard to make a multifunctional polymer avoiding the chiral centers. If we do not control stereochemistry, the combination of these centers will make unpredictable shapes. We cannot afford unpredictability. So it has to be perfectly controlled. The simplest way is to have everything of one kind. There is another problem. To make something you need to know how to make it, that is you need to store the information needed to make things. It is important that this information changes slowly, as otherwise things will go out of hand; some variation is good, but it should be a relatively rare occurrence. The machine should know what it is doing. Can we use the same polymer? Not really. We’ve picked our polymer to do chemistry. Doing chemistry is messy: you make reactive intermediates that once in a while ruin the machine. That’s not a big problem: the machine can be sacrificed and a new one made, but we do not want to risk our stored information, so we arrive at a two-polymer solution: one is for doing chemistry and having reactive groups, another as inert as reasonably possible and used only for storage and reading of the information. It should be resistant to light, radiation, dehydration, etc. It should also be easy to copy. Complementary linear chains are a good choice. If it is a helix, it provides additional structural stability. And so it goes… It is a rational process.

When you study biochemistry, this kind of thinking occurs very naturally: it is immediately seen that what you study is a design, and the way it is put together makes a lot of sense. If you’d know your science well and set yourself to the task of making the ideal geoengineering machine, you’d be driven towards similar solutions found in a living cell. It would not be exactly the same thing, but no two chemical plants are exactly the same. The principles and the ideas would not be dissimilar. That is the problem of the intelligent design as I see it. Can we show that this is not the case? — that the first cells were not these “cells”? Observe that such an introduction can be random: one may want to terraform as many planets in one’s vicinity as possible, taking chances: there was nothing special about Earth. I have little doubt that life did not originate on Earth, but then it is a pertinent question where it originated and what is it, really. We may well be someone’s design, and no Occam’s razor can eliminate this possibility, as it is THE simplest explanation of what one finds in a cell. We know absolutely nothing about this mysterious designer except that it did its job pretty well. On the most fundamental level, the design has never been radically changed. A lot of thought, foreplanning, and decision making was put into it. So it is fair to say that we are created by a rational agent. Beyond that, it is hard to tell. Perhaps this agent was no closer to us than we to our own chemical plants. It is hard to believe that life started in a form as complex as a cell. Perhaps life can exist in a much simpler form that is very different indeed.

A robotic mission left on the Mars would be our own intelligent design. Its robotic descendant may believe that their ancestor evolved from non-living matter, and they may even consider us as such matter. That would not change the fundamental fact that this ancestor had been designed, and part of this design was the ability to have descendants speculating on their own origin. Inventing the scenarios by which a TV camera could’ve “naturally” come together looks to me a waste of time. One’s ideology may force one to fancy such pursuits, but that’s faith. There is no basis for entertaining such beliefs.

I cannot imagine how can one disprove the idea that terrestrial life has been designed. We cannot and would never be able to determine what happened 3.5 Gya. Note that I’ve made it up that the goal of the unknown designer was geoenginnering. What was its real goal, only the designer might know, if it is still around. Or whoever knows what Life is, what is it for, and through which process the designers emerge. I am afraid that such matters are known only to the one who designed THAT process.

Have the terrestrial life been designed? What does it, actually, mean: the intelligent design?