Probabilistic Design
by JJS P.Eng.Approximately thirty years ago, the design methodology for structural engineers was deterministic. Discrete values were used to define loads/demand (D) and resistances/capacity (R). In the Working Stress Design method (WSD), a design was considered satisfactory if the ratio of R to D (representing the nominal resistance and nominal demand, respectively) was greater than or equal to a prescribed factor of safety, whose minimum value was based on engineering experience and was different depending on the structural element being designed. There are drawbacks to the WSD method*, one of which is it doesn’t adequately account for the variability inherent in R and D.
Today, most structural engineers incorporate probabilistic design into a new design philosophy called Limit State Design (LSD). From my graduate class notes:
“[LSD] is a design philosophy that requires the designer to recognize the various limit states for his/her structure and design to reduce the probability of each of these limit states being exceeded to an acceptably low level.”
It is now widely recognised that there are uncertainties in determining both R and D. Uncertainties in D (loads/demand) are due to the fact that they may vary depending on location and time (eg. there are no snow loads in summer, change of use). Different types of loads acting in combination serve to increase the amount uncertainty. There are three main factors that affect uncertainties in R (resistance/capacity): geometry, material properties and theory. The geometry of the member may be different than assumed during design (this is especially commonplace for cast-in-place concrete members). Similarly, material properties, such as strength, may be different than assumed. The strength of the member is determined using simplified equations that may not exactly represent the behaviour, which can be quite complex.
The range of values for R and D are assumed to be represented by lognormal distribution curves (See Figure 1). This assumption has been found to be reasonable because of the control of material properties and positive skewness of known load distribution curves. When R and D are plotted on the same graph, the location of the non-zero probability of failure is the region where the two curves overlap (D > R). This method of determining the likelihood of failure is known as statistical interference.
A convenient way to assess the probability of failure (D > R) is to consider a single lognormal distribution curve called the safety margin or S, where S = R – D (see Figure 2). The portion of the curve on the negative side of the graph (D > R) represents the probability of failure. This location is bound by bsS where b is the safety or reliability index and sS is the standard deviation for S. Figure 2 implies the higher b is, the lower the probability of failure will be.
However, most engineers (including myself) prefer to use deterministic values rather than probability distributions in their design calculations. Thus, the LSD method uses nominal values of D and R that are multiplied by load and resistance factors, respectively, that incorporate a low probability of failure. For a design to pass, the factored resistance must be greater than or equal to the factored demand, or f R ≥ aD, where f is the resistance factor (generally less than 1) and a is the load factor (generally greater than 1). The equations for f and a are derived using the lognormal distribution curve S (Figure 2) along with statistical mathematics and algebra. Thus, when engineers use the LSD, they can use discrete (nominal) values for R and D while accounting for uncertainties using load factors that were developed using probabilistic design theory.
Now that we've seen how structural engineers make use of probability theory in their designs, let's shift gears a bit. Is it plausible that the engineering method used to design life's biodiversity was based on probabilistic design? A piece of supporting evidence is that several evolutionary mechanisms tend to be stochastic processes, which means their behaviour could be potentially represented by distribution curves (normal, lognormal, or other). Thus, these curves have the potential to be incorporated into an engineering design methodology to design the first life form to evolve according to a preconceived plan (i.e. design objective).
I’m not alone in suggesting probabilistic design could have been part of the engineering design method used by a front-loading engineer.
“Life’s designer may have also made an intelligent use of chance. …the bait could have been the entire cell, or set of heterogeneous cells. What the blind watchmaker could subsequently find was then constrained by the carefully chosen initial conditions. …life’s initial conditions [may] have been rigged by the design of the cell’s architecture and the choice of which components to employ.” (emphasis mine)
The Design Matrix, Chapter 7, p. 153
The terms “bait” or “baiting evolution” are mentioned (in one form or another) several times in Chapter 7. IMO, this suggests that a front-loading engineer could use stochastic properties of evolutionary mechanisms to design the structure of the first life forms to achieve certain design objectives (my apologies to Mike if this was not his intended message).
Let me be clear. I am not suggesting that probabilistic design was actually used by a front-loading engineer. I am only saying this is an intriguing, yet plausible, option that deserves a closer look.
*This is not to say that structures designed to WSD were unsafe and are ready to collapse at any moment. Quite the opposite: WSD would generally lead to “overly” safe, robust, and (more often than not) costly structures as compared to structures designed using LSD method.
January 15th, 2009 at 12:16 am
[...] January 15, 2009 by Michael Before getting into some neat similarities between SETI and The Design Matrix, I’d like to take a break and direct your attention to a couple of interesting blog entries over at Telic Thoughts. When I wrote the DM, I intended to offer engineers a prominent seat at the table and I am quite pleased to see that one engineer, JJS P.Eng., has looked in on the fun. [...]
Pingback by An Engineer in the Matrix « The Design Matrix — January 15, 2009 @ 12:16 am
January 15th, 2009 at 1:49 am
Whoever came up with the LSD method could have come up with a better acronym.
One of my challenges to biologists is as follows: Given a species S1 from an environment E1, how many generations G, or in what range of generations G1 to G2, will it take to evolve into a species S2, when placed in a new environment E2.
I usually get blank stares or weaselling.
I do believe that some biologists are laying the groundwork for such problems. E.g., I learned of the existence of a book An Introduction to Stochastic Processes with Biology Applications that sounds like it would at least lay the groundwork toward such scientific predictions.
But, out of the biologists I've conversed with on the internet or in real life, none expressed knowledge of attempts to make macro-evolutionary theory (MET) mathematically rigorous in this manner. To be fair, the real life biologists are often incapable of having rational conversations with somebody who so challenges MET, as they've been trained like Pavlov's dogs to expect anybody who is skeptical of MET to be ignorant of science and the scientific method.
And I am ignorant of any serious attempts to quantify macro-evolutionary theory in this manner. Assuming this reflects actual shortcomings in MET research, the state of the art in modern biology isn't yet capable of using stochastic properties of evolutionary mechanisms to predict future life forms, let alone design future life forms, let alone design new first life forms.
Intriguing idea, yes. But I think you're decades ahead of where the world is. Perhaps you should write a science fiction novel (this is not a slam), and hope that it inspires future scientists to work toward the objective you describe. This has been the path for other technologies, and it may be the best path to getting biologists to think outside their "who needs math when you have a good story" box. In any event, writing a novel will be a good way to get credit in the popular culture, should the method prove fruitful. (Sad commentary on popular culture.)
Comment by William Wallace — January 15, 2009 @ 1:49 am
January 15th, 2009 at 9:25 am
Speciation can happen in as short as one generation (polyploidy), or over centuries (chromosomal), longer (genetic drift), or not at all.
Britton-Davidian, Environmental genetics: Rapid chromosomal evolution in island mice, Nature 2000.
Probably because you're asking the wrong question.
Comment by Zachriel — January 15, 2009 @ 9:25 am
January 15th, 2009 at 10:04 am
WW:
That's easy: [G1,G2]=[x,y].
Comment by Raevmo — January 15, 2009 @ 10:04 am
January 15th, 2009 at 11:02 am
How about ULS for Ultimate Limit States or SLS for Serviceability Limit States? That work for you?
That's kinda vague, eh?
Comment by JJS P.Eng. — January 15, 2009 @ 11:02 am
January 15th, 2009 at 11:14 am
JJS:
What else did you expect when the question is posed in a kinda vague way?
Comment by Raevmo — January 15, 2009 @ 11:14 am
January 15th, 2009 at 11:25 am
Raevmo, I'll give you credit for answer part of WW's challenge (in a vague manner):
Any specific range you want to postulate? How about going out on a limb and make a specific prediction for G?
Comment by JJS P.Eng. — January 15, 2009 @ 11:25 am
January 15th, 2009 at 12:09 pm
JSS:
You can't be serious. Without specifics on S1, E1, S2, E2? Zachriel already indicated that the answer can range from G=1 to G=very large, depending on the specifics.
Suppose I ask you to build a bridge over river X. Can you give me a specific prediction for the amount of steel needed?
Comment by Raevmo — January 15, 2009 @ 12:09 pm
January 15th, 2009 at 12:31 pm
S1 is a self-replicating ribonucleic acid.
E1 any of those observed extra-cellular environments observed as hospitable to self-replication.
S2 a self-replicating proto-cell.
E2 a watery environment
Comment by Bradford — January 15, 2009 @ 12:31 pm
January 15th, 2009 at 1:27 pm
Let's reverse engineer the thinking:
Start with yeast = S2
An accomodating environment of choice suitable for yeast = E2
What are the prokaryotic organism candidates (the S1s) in the evolutionary pathway to yeast. Fill in the approximate value for the Gs.
Comment by Bradford — January 15, 2009 @ 1:27 pm
January 15th, 2009 at 2:13 pm
I'd like to hear about a new species evolving in one generation.
If you need specifics, S1 is a zebra. S2 is a domesticated population descendant from S1, Cicur Hippotigris Dolichohippus
, capable of being saddled, ridden or used as a draft animal:). E1 is Africa wild. E2 is an African barn with free food from humans. What is G1 and G2.
To get the conversation back on track, the point was biologists cannot make predictions about future events unless they have already witnessed them. For example, in the absence of previous experiments, biologists cannot predict what percentage of two populations of flies, split from one another, isolated, and feed different diets, will mate with each other if they are reintroduced into the same environment after N generations, except when previous experiments have been conducted, and the second experiment starts out with a virtually genetically identical founder population.
Compare this to other sciences, much more advanced, that can accurately predict the results of experiments never before conducted–even when the experiments are stochastic.
Well, maybe even this derails JJS's track.
Comment by William Wallace — January 15, 2009 @ 2:13 pm
January 15th, 2009 at 2:26 pm
You think?
It's an interesting challenge you have there, WW, but perhaps it needs its own thread. *nudging Bradford*
Comment by JJS P.Eng. — January 15, 2009 @ 2:26 pm
January 15th, 2009 at 3:36 pm
The question you should be asking is whether the engineering method used to design life's biodiversity involved anything in addition to probabilistic design, since pure, mechanical probabilistic design is the current prevailing theory.
Comment by don provan — January 15, 2009 @ 3:36 pm
January 15th, 2009 at 3:50 pm
That design can be manifested through mechanical processes is clear. The question left hanging though is how mechanistic processes were generated? We all agree selection is a stochastic process. What causes gave rise to cellular mechanical structures?
Comment by Bradford — January 15, 2009 @ 3:50 pm
January 15th, 2009 at 4:07 pm
Ah, yes, pure chance + time, or what I like to call the "Las Vegas" theory.
C'mon seven! Lucky seven! Let's roll!
Comment by JJS P.Eng. — January 15, 2009 @ 4:07 pm
January 15th, 2009 at 4:26 pm
Polyploidal speciation is common in plants, rare in animals. It can sometimes, but not always, result in immediate reproductive isolation. More typically, *establishing* a polyploid occurs in mixed populations over generations.
Rieseberg & Willis, Plant speciation, Nature 2007.
Husband & Sabara, Evolutionary dynamics of diploid-polyploid contact zone: insights into polyploid speciation, New Phytologist 2003.
One of the most fundamental aspects of Darwin's Theory was discovering that a "species" is not always a well-delineated category. During the period when one species becomes two, they may separate gradually so that there is no one point where you clearly have one species and another point where you have two, and closely related species may occasionally hybridize.
We directly observe evolution and its mechanisms, so we certainly expect they will continue in the future.
Your statement shows a misunderstanding of the scientific method. We predict future observations. We might predict an observation of a fossil, for instance.
Comment by Zachriel — January 15, 2009 @ 4:26 pm
January 15th, 2009 at 4:38 pm
Ignoring your incorrect assessment of my understanding of the scientific method (unless by "scientific method" you mean as practiced and defined by evolutionary biologists
, Popper be damned)–In the context of a "probabilistic design"…"used by a front-loading engineer", predicting fossils doesn't seem very useful. Predicting in advance what new species will look like, how long it will take to get there, and so on, seems more useful.
Comment by William Wallace — January 15, 2009 @ 4:38 pm
January 15th, 2009 at 5:07 pm
Don't ignore it. Address it. If an evolutionary biologist makes a prediction from theory and walks out into the Egyptian wastelands, looks in a particular strata, and pulls out a fossil of a cetacean with legs, is that a valid scientific prediction?
Yes, we would like to know when the next asteroid will hit Earth, but our ability to make such predictions is rather limited. (Therefore the Theory of Gravity has no scientific merit?)
We directly observe evolution. New, naturally-evolving species will be descendents of existing species. And you ignored an important aspect of speciation (as explained above), fundamental to Darwin's Theory.
Comment by Zachriel — January 15, 2009 @ 5:07 pm
January 15th, 2009 at 5:17 pm
I actually have to agree with Zachriel on this one. The slightest changes can produce the most drastic effects over time, so evolution may not be predictive as it relates to the when and what of speciation. This is merely an extension of chaos theory. The variables that are involved as natural environments interplay with organisms may be too sensitive to provide any predictive utility.
Comment by CJYman — January 15, 2009 @ 5:17 pm
January 15th, 2009 at 8:49 pm
WW:
Nonsense. Your ignorance is showing once again. Outcomes of experimental evolution have been predicted with mathematical models quite accurately de novo. Consider this paper for example:
Griffin et al. 2004. Cooperation and competition in pathogenic bacteria. Nature 430, 1024-1027.
You mean other sciences that study much simpler systems? Are there other sciences that study systems comparable in complexity to living organisms that are better at predicting? I don't think you realize, or perhaps you willfully ignore, the mathematical sophistication of models in modern biology. A lot of new mathematical methods, such as in stochastic processes, are motivated by biological questions. You seem to be blinded by your irrational hatred of everything related to evolution (hence presumably your frequent use of the word "evolanders").
Comment by Raevmo — January 15, 2009 @ 8:49 pm
January 15th, 2009 at 9:48 pm
What you should call "the prevailing theory".
Do you want us to make fun of your theory like that? Or do you want it taken seriously and actually weighed against the evidence?
Anyway, your whole point in this blog entry is that "C'mon seven, lucky seven" works for human engineers, so logically it's inconsistent of you to suddenly decide it's a silly idea when the same principle is incorporated into another theory.
Comment by don provan — January 15, 2009 @ 9:48 pm
January 15th, 2009 at 11:44 pm
Except that once we figure out the position of the object in space, we are able to predict where it will be at some future time, within some margin of error.
If I am able to look at a stock price at two points in time and am able to predict within some margin of error the stock price at an intermediate point in time, this is not that useful, especially in the context of JJS's a frontloading engineer who is intelligent enough to figure out the consequences of stochastic processes in advance. Predicting the price of a stock tomorrow would be much more useful (and the science behind predicting tomorrow's stock price is probably more accurate than predicting tomorrow's new species.)
I'll take a look at it. Usually I can't find Nature articles for free, but I just found it here.
Would like it even more if the title of the article didn't have the word "bacteria" in it.
I notice nobody is putting forth an answer (or even proposing a method that could be used to find the answer) to the Zebra challenge (which was a response to complaints that I wasn't specific enough).
But if you think evolutionary biologists
are on the brink of being able to make such predictions, then JJS's proposals might have merit.
I like evolution. It lead to my dog, who has bred into here traits that allow her to be trained to find and flush birds, and dutifully bring them back to me undamaged after I kill them. But she's still a dog.
Evolanders are Origin of Species thumping evangelicals who feel it is their duty to fight criticisms of macro-evolutionary theory from any person who is not a biologist–and if the criticizer is a biologist, evolanders feel it is their evangelical mission in life to discredit them.
Comment by William Wallace — January 15, 2009 @ 11:44 pm
January 15th, 2009 at 11:56 pm
Actually, don, I was making fun of the "prevailing theory".
This misinterpreting the comments of others seems to be a bad habit for you. For what ever reason, you don't seem to be able to differentiate between using chance (probabilistic design) and leaving chance on its own (pure chance). I think the difference between the two is crystal clear. I also believe I've demonstrated clearly how chance can be used, and implicit in the explanation is that it is significantly different from pure chance (a major component of the "prevailing theory"). Your failure to grasp this simple concept leads me to question your motives for commenting.
Comment by JJS P.Eng. — January 15, 2009 @ 11:56 pm
January 16th, 2009 at 12:00 am
OK. I just sent a couple of comments to the memory hole. 100% blame on Todd. Keep the schoolyard taunts to recess, Toddie.
WW, I sent your "Who is FMM" comment to the memory hole, as well, since it was a direct response to Todd's infantile comment. I hold you blameless.
As for your question, fmm is a frequent commenter here with plenty of interesting things to say.
Carry on.
Comment by JJS P.Eng. — January 16, 2009 @ 12:00 am
January 16th, 2009 at 9:23 am
Not answering the question just reinforces the suggestion that you don't understand the scientific method.
Comment by Zachriel — January 16, 2009 @ 9:23 am
January 16th, 2009 at 9:31 am
Large collections of weakly interacting bodies are very hard to predict. No one knows when the next asteroid will hit the Earth.
You are still very confused. We *directly* observe evolution, and can make many predictions. Start with something simple like the Lederberg Experiment.
Comment by Zachriel — January 16, 2009 @ 9:31 am
January 16th, 2009 at 10:08 am
I would agree that it is practically impossible for a Front Loader to predict the evolutionary trajectory with any significant detail. Consider the difference between a world with and without the mass extinction of dinosaurs.
Consider instead an Intelligent Gardner. She has learned that if She plants the seeds of life in fertile soil, life will evolve into a myriad of forms. So She travels from star to star planting seeds, knowing that some at least will lead to marvelous fruit. It looks just like evolution. Though She has little idea how each garden will develop, through experience She knows that some will flower into sentient life.
Now consider that Bacteria Rule. They constitute the most in numbers and mass on Earth, by far. They have already used their hosts (human guts) to make the first tentative steps into space. Soon Earth's Bacteria will populate the planets, then the stars!
Comment by Zachriel — January 16, 2009 @ 10:08 am
January 16th, 2009 at 12:27 pm
Zachriel:
I would agree that a Front Loader, having human limitations, would be unable to predict.
Comment by Bradford — January 16, 2009 @ 12:27 pm
January 16th, 2009 at 1:55 pm
As Clarke's third law states, any sufficiently advanced technology is indistinguishable from magic.
So, an ability to predict the destination of what we model as stochastic processes seems like magic to me–that is, apparently more challenging than predicting the location within a large sealed undisturbed room the precise location of a single perfume molecule 4 hours after the bottle of perfume is opened.
If the intelligent engineer did engineer life to evolve into what it is now, it seems just as likely that what appears to us to be stochastic is actually precisely calculable.
The Intelligent Gardner model seems possible, too.
Even so, if biologists cannot predict with any certainty whatsoever what direction a population of creatures in a controlled/specified environment will evolve, it ("it" being macro-evolutionary theory, not biology) truly is a primitive science.
Yawn. Keep repeating it if it makes you comfortable. But the supposed scientific prediction you offer (finding fossils in Egypt) is marginally better than my 7 year old saying, "Hey dad, let's go to Lake superior and find some Lake Superior agates," the family taking a road trip, walking the shore, and finding an agate.
But I did like your Intelligent Gardner idea.
Comment by William Wallace — January 16, 2009 @ 1:55 pm
January 16th, 2009 at 2:06 pm
Perhaps this analogy can help the discussion. When I design structures using probabilistic design as described above, I am subconsciencely (sp?) setting the probability of failure (Pf) at an acceptably low value. This is not the same as predicting what the precise probability of failure actually will be. Nor can the method be used to predict the precise moment of failure in a structure where D > R (load greater than resistance).
Does this help?
Comment by JJS P.Eng. — January 16, 2009 @ 2:06 pm
January 16th, 2009 at 4:02 pm
I assume that the probability of success is 1.0 minus the probability of failure. In the case of a bridge, not collapsing into the Mississippi is success.
Do you think this is very similar to the probability of evolving human beings? Or is success merely not universal extinction?
(BTW, I am doing my best to avoid a debate on the design practices you describe, design practices that are too often (ab)used and misunderstood in the world of electronic engineering. Just pointing this out because I have a bias against engineers treating every variable they come across as a random variable, as though making an assumption similar to what some corporate trainer made in class makes it so in the real world.)
Comment by William Wallace — January 16, 2009 @ 4:02 pm
January 16th, 2009 at 4:33 pm
Yes, an Omniscient Designer would be able to predict everything—by definition. Now try to respond to the point.
Perhaps the Designer's purposes are sufficiently vague that the mere existence of organic diversity is the goal. Consider the difference between a world with and without the mass extinction of dinosaurs. As long as the goal isn't humans in particular, then the Designer doesn't have to predict every possible contingent event. And by seeding multiple worlds, this increases the chances that at least some of the gardens will yield fruit of some kind.
Consider the difference between a world with and without the mass extinction of dinosaurs. Apparently, the trajectory was highly altered by the mass extinction, likely caused an extraterrestrial impact.
Handwaving. The Theory of Evolution makes many predictions in many different fields from geology to genetics. Start with something simple like the Lederberg Experiment which demonstrates that mutations are random with respect to fitness.
So determining where to find strata from the Eocene that were once a shallow sea, but are now out in the middle of a desert and discovering a complete skeleton of a marine organism, Basilosaurus isis, is "marginally better" than a 7-year old finding agates on the seashore. Do you really think that is a convincing argument?
Comment by Zachriel — January 16, 2009 @ 4:33 pm
January 16th, 2009 at 4:48 pm
Zachriel:
True. As an advocate of mind brain duality that is where my major focus would be if looking to link goals to humanity.
Comment by Bradford — January 16, 2009 @ 4:48 pm
January 16th, 2009 at 4:52 pm
Of course you were. And my response was to ask if you wanted us to treat your theory the same way you're treating the theory accepted by all biologists.
The mechanism of evolution is exactly like the probalistic approach to engineering except that organisms are directly subjected to an actual environment to see whether they succeed or fail instead of being virtually measured against a probability graph. The result is identical: designs that succeed are accepted, those that don't are rejected. For the same reason this leads to good designs when human engineers use it, it also leads to good designs when a mindless process does it.
I'm sorry I didn't explain this better, but I thought it was obvious. What made it obvious to me was this statement in the OP:
Perhaps I misunderstood what you were saying, but I thought you were suggesting that these very stochastic properties of evolutionary mechanisms that I'm pointing to might have been designed in by front loading. In other words, I thought that you were the one suggesting that this mechanism was potentially an actual example of probabilistic design built into evolution. But apparently I was mistaken. What did you mean by "evolutionary mechanisms"? I thought you meant something related to the stochastic process in evolution as we observe it.
Comment by don provan — January 16, 2009 @ 4:52 pm
January 16th, 2009 at 6:17 pm
Hi Zach,
I'm curious why you think that finding a cetacean in an ancient sea is any better than finding an agate in an ancient deposit of volcanic rock.
Comment by chunkdz — January 16, 2009 @ 6:17 pm
January 16th, 2009 at 6:30 pm
Presumably Zach assumed the child was predicting that agates would be found at that location because he's found them before at that location. If you are suggesting that the child, without ever being at that location, was predicting that agate could be found there because he knew it was an ancient deposit of volcanic rock and understood the theoretical reasons why agate would be found in such locations, then that would be a different matter, much more like finding a cetacean in an ancient sea.
Comment by don provan — January 16, 2009 @ 6:30 pm
January 16th, 2009 at 6:41 pm
Provan,
Actually, finding a whale in a place that's called "Valley of the Whales" because of all the whales that have been found there is a guess that probably any 7 year old could make. But let's do allow Zach to speak for himself.
Comment by chunkdz — January 16, 2009 @ 6:41 pm
January 16th, 2009 at 10:13 pm
For someone uninterested in the origins of marine mammals, it isn't any "better". Perhaps the 7-year old can use his collections of agates to reveal new scientific insights into his local geology. But,
William Wallace was handwaving.
Comment by Zachriel — January 16, 2009 @ 10:13 pm
January 16th, 2009 at 10:54 pm
From a layman:
Life has always been interesting to me. No, profoundly interesting.
If this master engineer is able to operate a front loader well enough to pack all of this data into the first molecule of life, wouldn’t it be just as easy for him to fashion the end product to begin with and avoid any possibility of something going wrong? i.e. the egg might not hatch.
For us, wouldn’t “occam’s razor” be relevant here?
The literature I have been reading indicates that evolution (random mutation/natural selection) has surely been working since the OOL albeit in the opposite direction to the commonly assumed vector.
I think it might be more profitable for us to try to find out what went wrong in the original design.
Finding out is the big question, and I must leave it to the more learned and the younger, since they have more time to correct their errors.
Comment by OLClark — January 16, 2009 @ 10:54 pm
January 17th, 2009 at 4:48 am
Understanding the theoretical background or previously finding one personally is not necessary to find agates. All one needs to know is that the agate's common name is "Lake Superior Agate," it looks cool when they're polished, and you live near enough Lake Superior (as was indeed the case for my seven year old).
It's like we speak two different languages.
Comment by William Wallace — January 17, 2009 @ 4:48 am
January 17th, 2009 at 9:38 am
What part of "a cetacean with legs" don't you understand?
Comment by Zachriel — January 17, 2009 @ 9:38 am
January 17th, 2009 at 11:42 am
Zach,
Can't say that I blame him if you're going to pull out the old double standard again.
You frequently admonish ID'ers that they need to make specific, distinguishing, and falsifiable empirical predictions in order to be taken seriously. Yet the standard you set for "The Theory Of Evolution" is that they find a whale fossil in a deposit of whale fossils – something you now admit is no better than finding an agate in a deposit of agates.
Your "prediction" is not specific, not distinguishing, and not falsifiable.
Popper is turning in his grave.
Comment by chunkdz — January 17, 2009 @ 11:42 am
January 17th, 2009 at 1:50 pm
There was something different about this particular cetacean. A certain je ne sais quoi.
Comment by Zachriel — January 17, 2009 @ 1:50 pm
January 17th, 2009 at 6:04 pm
No doubt. Agates come in many different sizes, shapes and colors too.
IZNT SIENS KUL?!?
Comment by chunkdz — January 17, 2009 @ 6:04 pm
January 17th, 2009 at 7:04 pm
chunkdz wrote:
Funny. Here's a quote from Isaac Newton:
Comment by olegt — January 17, 2009 @ 7:04 pm
January 17th, 2009 at 11:45 pm
Someone please tell me the prediction thing with legs is not Tiktaalik.
What about the 2008 discovery of complete dissarray and misclassification of 1000s of supposedly different species? Now determined to be duplicates in 16% of known cases so far?
http://www.nature.com/news/2008/080917/full/news.2008.1111.html
Why are classification systems so messed up in a billion dollar business? It appears this field of science lacks any oversight, accountability, or proactive administration and accurate systems technology. The administration of such a klunky classification system seems as old and dusty as the bones they collect. But boy they'll tell u their hypothesis on camera and demand millions in funding for new species found.
Essentially 16% of declared species are not new, but simply duplicates of other species. What a quack job. It appears a PhD in bone collecting means u get to name your own Bonehead after your name or other charm. And millions are paid for such poor performance? Why? Is there no malpractice? No malfeasance?
Is there any other area of science so incapable of accurate data analysis? Why aren't these bones digitally analysed and available to the public for viewing? Our tax dollars pay for most of these collections yet we see next to nothing of real live analysis online of these bones, including Tiktaalik.
And I see no benefit from it for me except wild hand waving and more skull duggery stories of man walking out from the swamp a billion years ago. This is worthless science. I'm tired of my taxes going to such an inexact subjective hack job by ill-trained intellectuals who cannot clean up their dustbin of history.
Frankly, I can do what these guys do, find a clam and name it a new species. ClamDollaris RipOffArticus TaxPayortus
I'll have a book and National Geographic Special in Fall 2009.
Comment by TeleAboveGround — January 17, 2009 @ 11:45 pm
January 18th, 2009 at 10:46 am
* Tiktaalik is not the subject.
* Tiktaalik is not a dinosaur.
* Tiktaalik is definitely a new species.
* Tiktaalik satisifies the evolutionary prediction of an organism that exhibits intermediate characteristics between fish and land vertebrates (gills, scales, functional wrist, fins, primitive stapes, ribs, flexible neck and lungs).
Comment by Zachriel — January 18, 2009 @ 10:46 am
January 19th, 2009 at 3:12 pm
I really don't care how you treat "my"
theoryhypothesis. I only care about constructive critiques of the hypothesis, something in which you are sorely lacking.Saying you misunderstood is quite the understatement. Nowhere did I say the stochastic evolutionary mechanisms themselves were designed, but rather they were used as a design tool.
Sorry if I sound insulting, but IMO, I made this crystal clear in my post:
To sum up (again), a front-loading engineer could have used the stochastic properties of evolutionary mechanisms to design the first life forms (single celled). The evolutionary mechanisms are what they are, and some basic assumptions of FLE are they (the mechanisms) were known to the front-loading engineer and that he/she used them as a design tool, not that he/she designed the actual mechanisms.
Can we move on now?
Comment by JJS P.Eng. — January 19, 2009 @ 3:12 pm
January 19th, 2009 at 3:21 pm
JJS:
Presumably the very first life forms didn't have a flagellum. So if FLE is true, without further intervention, then it is possible after all that flagella can evolve by the (partially stochastic) mechanisms of evolution. In other words, IC and CSI are useless concepts. You gotta love how the various branches of ID contradict each other.
Comment by Raevmo — January 19, 2009 @ 3:21 pm
January 19th, 2009 at 3:32 pm
Raevmo:
As long as a few essentials are front loaded the flagella could evolve.
I dunno. Where did the genetic information, allowing for replication capacity and a few other features essential to basic life, come from?
Introduce a few uncertain assumptions into an analysis and apparent contradictions become much easier to point out.
Comment by Bradford — January 19, 2009 @ 3:32 pm
January 19th, 2009 at 3:55 pm
Raevmo,
You talk as if contradiction is a bad thing. I'd be more wary of the certainty of consensus.
Comment by chunkdz — January 19, 2009 @ 3:55 pm
January 19th, 2009 at 3:58 pm
Neither CSI nor IC tell us where the genetic information came from.
Comment by don provan — January 19, 2009 @ 3:58 pm
January 19th, 2009 at 4:00 pm
They are descriptive devices not answers. Go ahead and give us the answers.
Comment by Bradford — January 19, 2009 @ 4:00 pm
January 19th, 2009 at 4:03 pm
Contradiction is a bad thing. Disagreement can be productive, of course, but these contradictions do not reflect disagreement.
It's true that consensus is not a certain indicator of correctness, but it is way more reliable than contradiction.
Comment by don provan — January 19, 2009 @ 4:03 pm
January 19th, 2009 at 4:10 pm
Weren't you saying you didn't know whether they were useless because of the question you gave? If so, how do they help answer the question? If not, why did you bring up that question in response to someone saying they were useless?
What makes you think I have any answers?
Comment by don provan — January 19, 2009 @ 4:10 pm
January 19th, 2009 at 4:39 pm
I guess the reason I can't understand this is that I have no clue what "evolutionary mechanisms" means when you use the term to apply to something that exists before "the first life forms". Maybe you could clarify that.
Well, sorry about that. I don't really understand your hypothesis well enough to offer any input on it, constructive or not. I'm trying to ask questions about it, but you seem to take anything I ask as a knock.
Of course you do care how I treat it. You'd lock me out if I was disrespectful, which is perfectly reasonable.
Apology accepted.
Comment by don provan — January 19, 2009 @ 4:39 pm
January 19th, 2009 at 4:45 pm
You have plenty of opinions then.
Comment by Bradford — January 19, 2009 @ 4:45 pm
January 19th, 2009 at 4:50 pm
Evolutionary mechanisms: gene duplication, genetic drift, natural selection, etc.
Works for me. Consider it done.
Comment by JJS P.Eng. — January 19, 2009 @ 4:50 pm
January 19th, 2009 at 6:28 pm
Provan,
Consensus is not an indicator of correctness at all.
History refutes your assertion.
Comment by chunkdz — January 19, 2009 @ 6:28 pm
January 19th, 2009 at 7:23 pm
chunkdz:
If different persons hold opposing viewpoints, that's fine. But if a single person holds contradictory views simultaneously (i.e. FLE and IC), then that person logically should believe in everything, since it is a principle of logic that a contradiction implies all propositions.
Comment by Raevmo — January 19, 2009 @ 7:23 pm
January 19th, 2009 at 7:40 pm
IC and FLE are not contradictory notions. You can segment a timeline and find front loaded genes for subsequent developments. You can connect the segments to show continuity spanning great parts of the tree. You can even argue convincingly that an initial bare bones genome would have been irreducibly complex without contradiction. I quoted Dembski from his book No Free Lunch to emphasize that IC argues that recognizable physical pathways to irreducible complexity are plausible when Darwinian pathways are not. Then of course there is the possibility of deliberate tinkering to effect a purposeful outcome (giving Raevmo the opportunity for a potshot at religion).
Comment by Bradford — January 19, 2009 @ 7:40 pm
January 19th, 2009 at 7:51 pm
Bradford:
You seem to be suggesting now that multiple front-loading events have occurred, contradicting earlier statements that FLE posits a single front-loading event, namely the introduction of the first life forms on earth. So which is it? Single event of multiple events?
[by the way: why is everything bold?]
[PS2: hey, it suddenly isn't anymore]
Comment by Raevmo — January 19, 2009 @ 7:51 pm
January 19th, 2009 at 9:41 pm
Raevmo:
Not so. I was suggesting that an analytical approach, meant to gather evidence for front loading, could be segmented so as to evaluate different parts of the tree one study at a time and then connect the big picture in the end.
Comment by Bradford — January 19, 2009 @ 9:41 pm
January 20th, 2009 at 4:52 am
Bradford:
So there was a single front-loading event?
Comment by Raevmo — January 20, 2009 @ 4:52 am
January 20th, 2009 at 8:16 am
Raevmo
Not to speak for Bradford but I see no conflict between Frontloading and IC. In this very thread the difficulty of frontloading something as specific as humans been discussed.
Perhaps all the designer frontloaded the first organism with enough information make the planet hospitable for higher life forms for example and later introduced a mechanism to insure the advent of consciousness if that was his goal
peace
Comment by fifth monarchy man — January 20, 2009 @ 8:16 am
January 20th, 2009 at 8:41 am
fmm:
You see no conflict because there is none. Please loan your lenses to Raevmo.
Comment by Bradford — January 20, 2009 @ 8:41 am
January 20th, 2009 at 9:04 am
Bradford:
You didn't answer my question: was there a single front-loading event, or more?
Comment by Raevmo — January 20, 2009 @ 9:04 am