# 12

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Today's post, But There's Still A Chance, Right? was originally published on 06 January 2008. A summary (taken from the LW wiki):

Sometimes, you calculate the probability of a certain event and find that the number is so unbelievably small that your brain really can't keep track of how small it is, any more than you can spot an individual grain of sand on a beach from 100 meters off. But, because you're already thinking about that event enough to calculate the probability of it, it feels like it's still worth keeping track of. It's not.

Discuss the post here (rather than in the comments to the original post).

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However the simple evidence of the similarity in the genomes should have been very convincing. [That evolution had taken place and that chimps were related to humans]

I don't think so. If I were designing a bunch of living things, I would do a lot of reuse. I'd pretty much design each separate animal by modifying the design of other animals like it.

So I'd wind up with chimps and humans having a lot of overlap in their genome, too. Even with a designer instead of an evolver.

[-][anonymous]9y 6

If I were designing a bunch of living things, I would do a lot of reuse. I'd pretty much design each separate animal by modifying the design of other animals like it.

But would you only sample from one ancestor? Why, when we were adapted from climbing trees to running on the savanna, did our designer elect to twist chimpanzee feet into some weird new shape instead of just borrowing the feet from ostriches or something?

I'm a programmer and an engineer I don't buy this re-use argument. When I make a new design, I sample from everything I possibly can, not a single predecessor. Also, if I were designing a whole multitude of things, there would be a lot more orthogonal modularity and a lot less tree structure. And probably some level of purpose in the designs.

The tree structure is very much strong evidence for unintelligent evolution.

I think you are right, but overstating it. That is, the tree structure is an argument for "local only" communication, as you say, why don't bird feet show up in any mammals and so on. Why are the changes across the tree incremental (which incrementalism is how we can connect adjacent nodes in the tree structure).

We do see a little bit of this in car designs. For modern cars one would have the major phyla which might be the brands, or possibly even the manufacturers. Within a given manufactured platform, there would be many similar offerings where the platform is adapted for different marketing organizations. Then somewhat more differentiation, the SUV model on some basic platform that also supports a 2 door and a 4 door, and so on. Then the more distant relationships with engines across different offerings, still limited (primarily) to within the manufacturers branches. Finally some features of engines like "hemi heads" on multiple chrysler engines, presumably some other features would be like this.

So yes, broad communication across all the individual types suggests a single intelligence reusing what it wants where it wants to. But we still have intelligent design in cars and something of a tree structure. So it doesn't seem dispositive.

[-][anonymous]9y 2

You can always do fast footwork and add epicycles, but by the time any theory predicts the observed tree structure as strongly as evolution does, it effectively is evolution. If the tree structure is not strong evidence for evolution, nothing is strong evidence for anything.

Cars are not tree-structured. There are a bunch of orthogonal variation dimensions. cars share frame technologies, engine technologies, tire technologies, etc. different companies have highly similar designs.

I don't think so. If I were designing a bunch of living things, I would do a lot of reuse. I'd pretty much design each separate animal by modifying the design of other animals like it.

Well, yes, because you're not omnipotent. Once you have unlimited knowledge and unlimited power, the optimal design strategy for you looks quite different from that of a modern engineer.

What we know of intelligent design (in lower case, not the origin myth with that name) is a bunch of stuff including various economies of design processes and elegance of design processes. Reuse and standardization of components and subsystems have to be among the top principles of design.

So at bare minimum, similarity between chimp and human (and bonobo and gorilla and pig and rat) genomes hardly rules out an intelligent design process, the reuse in fact would more reasonably be thought a hallmark of intelligent design process.

Which is not to say that I don't credit natural and sexual selection among mutations as the most probably correct theory as to how we came about. But the economy of effort that reuse provides, it provides to designers intelligent and unintelligent alike.

To reiterate, my point being this is not a point in favor of evolution over intelligent design.

Second: how is it meaningufl to invoke an omnipotent designer as a naked unsupported claim that while all the designers we know (unintelligent and finite intelligence) would follow these economies of design, an omnipotent one would not? Don't you need to flesh out your theory as to why an omnipotent designer would not reuse and design incrementally?

I'll help out by telling you why I think an omnipotent designer WOULD do reuse. When the omnipotent designer designs, blood, or bone, or ATP-ATG cycle or a neuron for a particular purpose, being unconstrained, presumably this designer goes for the true optimum given whatever constraints he has decided to put on himself in this design. When he then is designing a family of creatures, each creature that uses that subsystem will want that fully optimal version. So in this case, reuse occurs not because the designer has finite energy, but because the system being reused is the optimal design for that system.

So what is your theory of an omnipotent designer that RULES OUT an optimum designer using reuse, just like all the known designers (intelligent and unintelligent) already do?

The primary reason humans reuse previous inventions is that point of economy of effort. We have a limited amount of resources that we can invest in any one project. If we were capable of independently recalculating the optimum design for each project we work on, we would do better. In the worst case scenario, we find out that the same solution that applied to our last problem also solves the one we're currently working on. But fairly frequently, we would find that there are different optimum strategies for different problems, and in those cases, we would do better. However, the gains would be small enough, and the frequency of this occurring would be low enough, that it is not worth pursuing this strategy with limited resources. If we had infinite resources, the cost of pursuing this strategy would drop to zero, and thus the expected utility would be positive.

I do think it is plausible that the same strategy would be reused because that strategy is optimal, but only in certain conditions. Namely, both strategies would have to be optimized for the same constraints. ATP is a fine source of energy, but any organism that wished to use inorganic phosphate ions for any other purpose would likely be better served with a different energy molecule. But, cells which do employ phosphate ions for biosynthesis purposes still employ glycolysis (and electron transport methods) to produce ATP.

For a more blatant example, it seems unbelievably improbable that the optimum anatomical design would be so incredibly similar between small, tree-dwelling herbivores(monkeys), ground-dwelling omnivores (apes), and the rational beings created to love and worship their creator.

For a more blatant example, it seems unbelievably improbable that the optimum anatomical design would be so incredibly similar between small, tree-dwelling herbivores(monkeys), ground-dwelling omnivores (apes), and the rational beings created to love and worship their creator.

WHy would god create imperfect beings anyway? I think if you are going to play this game you have to either realize you have no idea what god's motivation (or in engineering jargon, requirements) are, and therefore you don't have much way to complain when her design recapitulates things we might do as finite designers. That we are imperfect certainly is an argument against an omnipotent omniscient god creating us, but only if you think that this god gives a crap about what we think of her choices and motivations.

I personally find the omniscient omipotent omnigood creator ridiculous pretty much for these reasons. But once "inside" the system, I don't think an economy of design energy is a particularly great place to hang my "and furthermore" hat.

Perhaps omnipotent god uses an efficiency of design because she would rather use her infinite resources to create a higher order of infinity of different sorts of intelligent beings all over the multivers than to do a really obsessive-compulsive job on just a lower-order of infinity of worlds like earth. Who knows.

Sometimes, you calculate the probability of a certain event and find that the number is so unbelievably small that your brain really can't keep track of how small it is, any more than you can spot an individual grain of sand on a beach from 100 meters off. But, because you're already thinking about that event enough to calculate the probability of it, it feels like it's still worth keeping track of. It's not.

This seems to contradict the point of the Einstein's Arrogance post.

I had thought of Einstein's Arrogance as being about the enormous amount of unstated and perhaps unconscious bayesian evidence Einstein had that his model was correct. I'm not making the inductive step from there to "just forget about winning the lottery."

edit: I just realized the reading that makes sense: If you calculate the probability of a certain event, and the number is unbelievably small, you probably made a mistake in your calculations; or your intuition wouldn't have brought up the event in the first place.

I think there's plenty of room for both to be correct: Your intuition is evidence, but if you make an explicit probability calculation and it contradicts your intuition, be aware that due to a number of biases, you're still likely to overweight the probability.