Thank you Justin for your reasonable discussion on the subject of evolution. This is rare indeed on these discussion forums. I will now respond to your previous comment about the "analogy".
Originally Posted by JustinFoldsFive
Your analogy is flawed. Using your analogy, one must know what constitutes a "meaningful sentence" prior to the point at which you change a letter. There is no such prior knowledge requirement when it comes to evolution. With evolutionary theory, the result of the mutation (letter change) is a meaningful intermediate sequence, so long as the organism survives. If the mutation is not beneficial (or even harmful), the organism will die, and will not constitute a meaningful intermediate sequence.
First, it is not exactly my analogy. The analogy was first presented by Richard Dawkins in his classic work The Blind Watchmaker. It was his analogy with evolution that was flawed, I simply have made a slight change to it to correct his flaw.
Dawkins was demonstrating how easy to would be for random changes plus natural selection to create a particular sentence METHINKS IT IS LIKE A WEASEL.
His flaw was twofold. His example started out with a random string of characters of the same length as the sentence mentioned above. He wrote a computer program which would randomly change a letter in a random position of the "in-process" sentence.
At each step of a step-by-step process the program would check to see if the "proposed" new letter matched the "target" sentence at the corresponding position in the sentence.
This approach he declared, was analogous to Natural Selection.
His computer program when run rapidly converged to the desired "target: sentence, proving that random mutations plus natural selection worked.
I presume that you are perceptive enough to detect the multiple flaws in his analogy compared to what happens in the real world with mutations to DNA which then become exposed to the environment around a living creature.
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My modifications of Dawkin's analogy.
First let me say that the idea to use language as an analog to DNA and life is a brilliant one. But like many brilliant ideas, concepts are sometimes garbled in their detailed implementation, so that subsequent investigators may need it modify the detailed implementation.
The first flaw is that evolution, as opposed to abiogenesis, does not presume that evolution began with random strings of DNA. Instead they logically start with a working lifeform of some sort. Therefore, I modified the analogy to start with a working (feasible) or meaningful sentence, which of course is the analog of a string of DNA, a gene, which codes for a working string of DNA which in turn will eventually generate a "working" protein. (A "working" protein is one which folds into something loosely thought of as a ball, which then has a function, because proteins which fail to do this are essentially without function)
The second flaw of the original analogy was the assumption of a "target" string of letters that the step by step process is working towards, i.e. the selection process in the computer program "knew" what the answer should be and rejected any in-process string of letters which did not "work" toward advancing the process toward the desired goal.
The next step here consisted of compiling a list of all possible words in the English language, one, two, three, etc. letter words. This was a prelude which is not actually used in the analogy as such, but is include merely to illustrate that not all sub sequences of letters in a sentence are feasible (sentences are composed of words).
The second step in correcting the orginal analogy was to recognize that the "selection" had to be more analogous to natural selection, which is to say that it cannot have a "target" sentence that it is working toward. The selection process here will simply look at the in-process sentence and determine whether a new "working" string of letters has resulted from a random change to one of the letters in the old sentence (the "in-process" string). If not then the new working string of letters is discarded (killed). This is more analogous to what happens in nature, where "mutants" (failures) die, because they fail to work properly. Their DNA fails to code for a properly functioning protein, which in turn cripples some bodily function which in turn makes them less fit to survive.
The third correction step is actually the same as the second, but is mentioned to illustrate an additional flaw in the original analogy. Specifically, an "in-process"string of letters that doesn't mean anything should not be retained just because some of its letters happen to match a future "target" sentence. Natural Selection cannot look ahead to some future desirable target. Thus, in the modified analogy, an "in-process" string is not retained simply because it might prove to be useful at some time in the future. It is only retained if it works immediately, meaning in this case that it is a new sentence which has discernable meaning (using the observer as an analog of natural selection).
At this point let us review your criticism of my "revised" Dawkin's analog.
Originally Posted by JustinFoldsFive
Your analogy is flawed. Using your analogy, one must know what constitutes a "meaningful sentence" prior to the point at which you change a letter. There is no such prior knowledge requirement when it comes to evolution. With evolutionary theory, the result of the mutation (letter change) is a meaningful intermediate sequence, so long as the organism survives. If the mutation is not beneficial (or even harmful), the organism will die, and will not constitute a meaningful intermediate sequence.
What you are saying here seems to me to be equivalent to the points I was making regarding Dawkin's analogy, and led me to revise his analogy to be more realistic.
You said, "one must know what constitutes a "meaningful sentence" prior to the point at which you change a letter."
Although this is true I fail to see that it is relevent to the revised analogy. Natural Selection knows what is "meaningful", as does the observer of an English sentence who is acting as the analog to Natural Selection. Anyone familiar with the English language can easily detect when a sentence "does not work".
I await your reply with anticipation, but please do not neglect your studies for my sake. I will be patient, so please do not feel pressured to draft an immediate reply if this does not fit your immediate schedule.
