08 August 2010

The God of Evolution

Eliezer Yudkowsky has written an interesting post about how we  humans tend to incorrectly (in his view) attribute coherent purpose to the process of biological evolution, which leads to an incorrect assumption about the type of god that would design such a system. While I suggest you read the whole thing, here are some excerpts. 


Why is so much of nature at war with other parts of Nature?  Because there isn't one Evolution directing the whole process.  There's as many different "evolutions" as reproducing populations.  Rabbit genes are becoming more or less frequent in rabbit populations.  Fox genes are becoming more or less frequent in fox populations.  Fox genes which construct foxes that catch rabbits, insert more copies of themselves in the next generation.  Rabbit genes which construct rabbits that evade foxes are naturally more common in the next generation of rabbits.  Hence the phrase "natural selection". 






Why is Nature cruel? 







You, a human, can look at an Ichneumon wasp, and decide that it's cruel to eat your prey alive.  You can decide that if you're going to eat your prey alive, you can at least have the decency to stop it from hurting.  It would scarcely cost the wasp anything to anesthetize its prey as well as paralyze it.  Or what about old elephants, who die of starvation when their last set of teeth fall out?  These elephants aren't going to reproduce anyway.  What would it cost evolution - the evolution of elephants, rather - to ensure that the elephant dies right away, instead of slowly and in agony?  What would it cost evolution to anesthetize the elephant, or give it pleasant dreams before it dies?  Nothing; that elephant won't reproduce more or less either way...
 
Human beings fake their justifications, figure out what they want using one method, and then justify it using another method.  There's no Evolution of Elephants Fairy that's trying to (a) figure out what's best for elephants, and then (b) figure out how to justify it to the Evolutionary Overseer, who (c) doesn't want to see reproductive fitness decreased, but is (d) willing to go along with the painless-death idea, so long as it doesn't actually harm any genes...
There's no advocate for the elephants anywhere in the system.

Humans, who are often deeply concerned for the well-being of animals, can be very persuasive in arguing how various kindnesses wouldn't harm reproductive fitness at all.  Sadly, the evolution of elephants doesn't use a similar algorithm; it doesn't select nice genes that can plausibly be argued to help reproductive fitness.  Simply: genes that replicate more often become more frequent in the next generation.  Like water flowing downhill, and equally benevolent...

The human retina is constructed backward:  The light-sensitive cells are at the back, and the nerves emerge from the front and go back through the retina into the brain.  Hence the blind spot.  To a human engineer, this looks simply stupid - and other organisms have independently evolved retinas the right way around.  Why not redesign the retina?

The problem is that no single mutation will reroute the whole retina simultaneously.  A human engineer can redesign multiple parts simultaneously, or plan ahead for future changes.  But if a single mutation breaks some vital part of the organism, it doesn't matter what wonderful things a Fairy could build on top of it - the organism dies and the genes decreases in frequency. 
If you turn around the retina's cells without also reprogramming the nerves and optic cable, the system as a whole won't work.  It doesn't matter that, to a Fairy or a human engineer, this is one step forward in redesigning the retina.  The organism is blind.  Evolution has no foresight, it is simply the frozen history of which organisms did in fact reproduce.  Evolution is as blind as a halfway-redesigned retina. 

In a lot of ways, evolution is like unto theology.  "Gods are ontologically distinct from creatures," said Damien Broderick, "or they're not worth the paper they're written on."  And indeed, the Shaper of Life is not itself a creature.  Evolution is bodiless, like the Judeo-Christian deity.  Omnipresent in Nature, immanent in the fall of every leaf.  Vast as a planet's surface.  Billions of years old.  Itself unmade, arising naturally from the structure of physics.  Doesn't that all sound like something that might have been said about God?

And yet the Maker has no mind, as well as no body.  In some ways, its handiwork is incredibly poor design by human standards.  It is internally divided.  Most of all, it isn't nice. 
In a way, Darwin discovered God - a God that failed to match the preconceptions of theology, and so passed unheralded.  If Darwin had discovered that life was created by an intelligent agent - a bodiless mind that loves us, and will smite us with lightning if we dare say otherwise - people would have said "My gosh!  That's God!"
But instead Darwin discovered a strange alien God - not comfortably "ineffable", but really genuinely different from us.  Evolution is not a God, but if it were, it wouldn't be Jehovah.  It would be H. P. Lovecraft's Azathoth, the blind idiot God burbling chaotically at the center of everything, surrounded by the thin monotonous piping of flutes.
This is thought provoking. I have always been conflicted about using examples from nature to provide evidence of God's benevolence and omnipotence. Yes one could argue that God provided buffalo so that we could be warm and fed, but what about the buffalo? Who advocates for the buffalo, itself a complex being that is very capable of feeling fear and pain? Yes nature is beautiful and infinitely complex and can provide useful symbolism for our spiritual growth, but very often it is cruel, indifferent, heartless, and oftentimes as the author points out, it serves no apparent purpose. I have often thought to myself, if the "purpose" of evolution was indeed to create human type consciousness which would draw closer to God consciousness, does the end really justify the means? That is, why couldn't God have designed humans like a watchmaker designs a watch? Why do their have to be so many undesirable, and well, horrific, elements built into the process, not just of ecological evolution, but also cultural evolution?

Yet on the other hand, I think that the writer makes a mistake in his complete confidence that humans are in the cognitive position to make a final judgement about the efficiency, and if not benevolence, then justice, of evolution. From our point of view as watchmakers, we might judge many things about evolution to be cruel and inefficient, but we are also ignorant of many things "objective" about reality, given our impressive but limited perceptual capabilities. How do we know that the starving elephant, who's suffering serves no added value to its reproductive fitness and thus gene replication, is not serving some other meta-purpose that we are unaware of. I know that it is kind of squirmy, as he points out, for religious people to use the "well, we don't know everything" argument in hopes that science will eventually vindicate their position. But, as a clergyman once said, absence of evidence is not evidence of absence. 

3 comments:

  1. Certainly, the process of natural selection is a fairly grave challenge to the enlightenment era image of God as a watchmaker. But when I look at the natural world, Azathoth is not the sort of image that comes to mind. There is order and security in nature, just not the sort that we're accustomed to within our society.

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  2. What do you mean when you say that there is order and security in nature?

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  3. Most organisms of most species are mostly well adapted to their environment and generally live in balance with each other. It's not seamless. There is pain and misery that's structurally consistant, as is the case with elephants losing their teeth. But for the most part everything is generally in a state of order.

    That's all.

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