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To: GodGunsGuts
PS You never did give me your thoughts on the following re: GA’s...

Yes I did. I said the author doesn't understand GAs. And it's painfully obvious to anyone who's actually programmed them that he is ignorant of how they work. There is no way to "address" his statements since he doesn't even define what a GA is properly; it would make as much sense as me demanding you to address how the spark plugs work in your bicycle.

39 posted on 05/09/2009 2:42:32 AM PDT by PugetSoundSoldier (Indignation over the sting of truth is the defense of the indefensible)
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To: PugetSoundSoldier
You mean "authors" plural. And I have yet to see you concretely address either one of them. Rather than post a link, I will post the excerpt in full. Now what about what Dr. Abel's comments with respect to GA's being irrelevant to evolution do you disagree with?

Genetic algorithms are irrelevant to evolution

David Abel, The Gene Emergence Project, The Origin of Life Science Foundation

12. What optimizes genetic algorithms?

Computational methods often employ genetic algorithms (GAs). The appeal of GAs is that they are modeled after biological evolution. The latter is the main motivation for tolerating such an inefficient awkward process. The GA search technique begins with a large random pool of representations of “potential solutions.” Genetic algorithms are seen as a subset of evolutionary algorithms and as “evolutionary computation.” The methodology is inspired by modeling a random beginning phase space, various kinds of mutations, inheritance and selection. The experimenter chooses the fittest solutions from each generation out of the “evolving” phase space of potential solutions. The goal of the process is optimization of a certain function.
All too many evolutionary computationists fail to realize the purely formal nature of GA procedures. GAs are not dealing with physicodynamic cause-and-effect chains. First, what is being optimized is a formal representation of meaning and function. A representation of any kind cannot be reduced to inanimate physicality. Second, “potential solutions” are formal, not merely physical entities. Third, at each iteration (generation) a certain portion of the population of potential solutions is deliberately selected by the agent experimenter (artificial selection) to “breed” a new generation. The optimized solution was purposefully pursued at each iteration. The overall process was entirely goaldirected (formal). Real evolution has no goal [refs.]. Fourth, a formal fitness function is used to define and measure the fittest solutions thus far to a certain formal problem. The act of defining and measuring, along with just about everything else in the GA procedure, is altogether formal, not physical [refs.].
Despite the appealing similarities of terms like “chromosomes”, GAs have no relevance whatsoever to molecular evolution or gene emergence. Inanimate nature cannot define a fitness function over measures of the quality of representations of solutions. GAs are no model at all of natural process. GAs are nothing more than multiple layers of abstract conceptual engineering. Like language, we may start with a random phase space of alphabetical symbols. But no meaning or function results without deliberate and purposeful selection of letters out of that random phase space.
No abiotic primordial physicodynamic environment could have exercised such programming prowess. Neither physics nor chemistry can dictate formal optimization, any more than physicality itself generates the formal study of physicality. Human epistemological pursuits are formal enterprises of agent minds. Natural process GAs have not been observed to exist. The GAs of living organisms are just metaphysically presupposed to have originated through natural process. We can liberally employ GAs and so-called evolutionary algorithms for all sorts of productive tasks. But GAs cannot be used to model spontaneous life origin through natural process because GAs are formal.


50 posted on 05/09/2009 9:51:15 AM PDT by GodGunsGuts
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To: PugetSoundSoldier
And it's painfully obvious to anyone who's actually programmed them that he is ignorant of how they work.

I've programmed computers since 1965. It is not obvious to me that he is ignorant of how they work. Richard Dawkins seems to think that the Weasel program is a genetic algorithm. At least he touts it as such. Plus there are many others who think so. Monash University, the largest university in Australia, teaches this.

Genetic algorithm weasel

In a genetic algorithm (GA) we try to evolve a population of candidate solutions to a certain problem. In this case we are trying to evolve a population of strings to match the line "methinks it is like a weasel".

I do not think that it is a scientific principle that nature tries to evolve a population to solve a certain problem. I think that is a hallmark of intelligence.

51 posted on 05/09/2009 9:59:49 AM PDT by AndrewC (Metanoia)
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