Posted on 06/15/2003 10:36:08 AM PDT by Alamo-Girl
And certainly, be as biased as you wish. And post your views to your hearts content on this thread. Please also post leads so people can do independent research at their leisure.
That is the wonderful thing about Free Republic, it allows people who havent made up their mind to see all the different points of view and arrive at their own conclusions.
This sounds to me more like symantics than substance. The reason mice are used in medical experiments is that we share 99 percent of the bichemistry of mice. What I find remarkable is that tiny changes in the blueprint make such huge differences in form and function. This is one of those profound differences between things that are "designed" and things arising through evolution. Living things have an enormous economy in their blueprints.
That may be. There are a number of emergent function type models out there (a la Wolfram--he wasn't first, you know!). But we don't have any molecular evidence for "other factor(s)". We haven't found a secret supergene, present from the time of the putative UCA, that hypermutates and recombines into genes, just so, in times of need. We haven't found a heavenly mosquito that injects the appropriate genetic sequences to allow for adaptive mutations. We haven't discovered any mechanisms that allow DNA repair systems to overlook specific mutations that will lead to new features. So, we are left with a model that supports genetic change on a probabilistic level that indicates no directed change even though we know there is bias based on structural, sequence information, developmental, or environmental constraints.
On top of all that, we already know, with massive amounts of supporting evidence, that natural selection that acts on variation exists. Any change, however it is induced, is subject to selection. Any other factors at work in evolution are still subject to selection.
Why would the primaeval fish "naturally select" for functions/capabilities that it didn't need to improve its survival fitness?
In other words, why are organisms evolvable? At one level because of the imperfection in replication. From a birds-eye view, that's a much larger question, of course. Why do the laws of physics and chemistry make it possible for this to happen? Why are things the way they are? I don't know if that's a question for which the answer can be found in evolution.
I think you missed my point. There are a vast array of organic chemicals in biology that all could have been the basis for an eye. And in fact, many have non-eye uses in biology. A photo-reactive system in biology is not particularly remarkable in and of itself, and for there to be one over another seems to be pretty arbitrary to me.
My objection is to the idea that "eyes" are remarkable from a biochemical standpoint. I would actually assert that the neural systems behind the eye are for more intriguing and difficult to explain. I don't have a lot of context for Schroeder's position, I only find it odd that he focuses on one of the least remarkable aspects of the whole thing and tries to paint it as more remarkable than it actually is.
What I'm saying is that Schroeder is going to great length to say that the bear dances badly and ignores the remarkable fact that the bear dances at all. I don't really have a beef with Schroeder, just with his odd priorities and perception of "remarkability".
Alamo-Girl, I have a number of questions. Starting with the above quote from Hawking: Do these statements appear as tautological to you as they do to me? What is that "therefore" if not the link between an untested premise, an assertion, and a conclusion based on it, with no evidence or other information given? One might say the conclusion is stated in the premise, period. There is no light shed on the origin of dynamical laws, though certainly they do appear to function "intrinsically" in the universe. They "just are." (Ask no questions about this.)
He goes on: "Although the laws of science seemed to predict the universe has a beginning, they also seemed to predict that they could not determine how the universe would have begun. This was very unsatisfactory." For Aristotle, the question never came up: the universe just always was; there was no "beginning." But given that the Big Bang theory -- which definitely sets a beginning -- seems pretty solid, it has to come up for Hawking. And to deal with a beginning is to deal with time. So he deals with the issue by postulating "imaginary time," so that we can have a beginning of the universe and its "intrinsic laws" without recourse to an extra-cosmic Prime Mover. He goes on:
"...if one knows the state of the universe in imaginary time, one can calculate the state of the universe in real time."
Yes; but -- how does one calculate the state of the universe in imaginary time? Continuing:
"One would still expect some sort of Big Bang singularity in real time. So real time would still have a beginning. But one wouldn't have to appeal to something outside the universe, to determine how the universe began. Instead, the way the universe started out at the Big Bang would be determined by the state of the universe in imaginary time. Thus, the universe would be a completely self-contained system. It would not be determined by anything outside the physical universe, that we observe." [Heaven forfend!]
But how can the universe be so dynamical, if it is thus so relentlessly "self-contained" -- a completely closed system of what boils down to inexorable self-reference, a kind of cosmic solipsism? This type of reasoning smacks of being yet another application of Hegel's "dialectical science," which was never about science, but only about "myth-making."
By what principle can Hawking access "imaginary time?" Does "imaginary time" match up with "imaginary space," and even "imaginary beings?" Is he going to rely on something like that funny little mathematical crittur, i, by which we ensure that we can do square roots of negative numbers -- a purpose-built operational construct, though clearly a useful one? Is physical theory detaching from the world of sensible (and measurable!) objects altogether these days?
Hawking seems to be quite an idealist. Which is a tad odd in a physicist, given the premises of science. I'll take Platonic realism any day....
Thanks for letting me ramble on here. The analogy to the biological materialist's quest of an explanation of the origin of Life by purely intracosmic means seems paralleled by Hawking with respect to the physical universe itself. Darwin took his intimate knowledge of animal husbandry and extrapolated abiogenesis from it. Looks like Hawking is doing something similar in his explanation of a universal beginning in imaginary time....
I read this statement and come up with the reverse sense than you do, probably because you used the word "blueprint." A blueprint is a model of economy; and blueprints are always designs. Living things arising in nature through evolution may do so according to a blueprint in precisely this sense. I don't think this possibility has been (perhaps cannot be) ruled out.
But this is my point, Nebullis. Does this then necessarily mean that because evolution cannot find the answer to these questions, then no answer can be found? And thus, we are to assume that, because we can't find the answers, then the questions do not make sense at all? So don't ask them?
If you think of genes as a program, you cannot predict their outcome except by running the program. I like to think of this as acause/effect system in which causation flows backwards in time. Selection causes some programs to have a reproductive advantage.
Perhaps God, existing outside time, is the ultimate selector. ;^)
But within the constraints of a system that perceives time as change rather than a physical dimension, the design of living systems is impossible, because you cannot foresee the consequenses of changes to your program.
Nebullis and I have been mulling around Pax-6 and the import of it. You might be interested in the articles linked and partially excerpted at post 184.
Evidently what astonished the researchers was that (emphasis mine)
Meaningful discussions of "fine tuning" must wait until we observe another universe to compare properties with. Only so much extrapolation can be done with a sample population of one unit.
No real comment, other than that in my limited experience his biochemical argument seems specious. But as I said, I'm not deeply familiar with his works, nor am I particularly interested in his arguments. I'm mostly defending the good name of computational organic chemistry, which I worked in many years ago. I generally find chemistry to make for boring discussions, hence why I do not work in the field despite my background. :-)
Stephen Wolfram questions the natural selection pillar of biological evolution
I actually think Wolfram is partially correct here. In fact, the idea of building functional complexity through automata rather than evolution predates Wolfram's thoughts on the subject. There is someone who is widely credited with the idea in theoretical circles, but I can't remember their name off the top of my head. I've stated for years here that there are other plausible natural mechanisms besides evolution for the increase in biological complexity. My personal belief is that it is a combination of both evolution (because some selection does obviously occur) and automata. Wolfram shouldn't really be given credit for this idea; he almost certainly borrowed it (like many of his other ideas) from the person whose name I cannot remember. I'll see if I can find it.
Luis Rocha questions the syntactic autonomy that gives rise to self-organizing complexity
No comment. He does interesting theoretical work, but his particular theoretical tangent works with some assumptions that have fallen out of favor (and for good reason) for the purposes of our discussion here. It is interesting from a purely theoretical standpoint, but not entirely relevant for our discussion.
H.H. Pattee questions the von Neumann challenge, what is the nature of this thing life
No comment. In an algorithmic information theory framework, his questions are essentially answered. He was not writing to this perspective (which I do write from), so I consider his questions not particularly relevant. If one takes a view from a non-AIT framework, his questions may still be relevant.
Hubert P Yockey questions the rise of life from non-life
The first guy on the list I have an issue with. In short, Yockey has a simplistic and incorrect understanding of information theory, and misuses it in his theorizing. He is not a credible source.
Marcel-Paul Schützenberger questions the rise of functional complexity
No comment. His particular perspective is somewhat narrow so as to exclude possibilities he doesn't consider, but I don't have any particular problem with him. I do think other people apply what he has said in a much broader scope than is valid.
Stephen Hawking questions the beginning of time
No comment. He is a credible physicist. Questioning the beginning of time isn't entirely relevant to any of our discussions here (and I think very few people grok "time" enough in a theoretical context to have meaningful opinion on it -- myself included).
Sir Martin Rees questions the rise of the six numbers which allow this universe
Not relevant, so no comment. The manner in which this type of fixation is irrelevant has been dealt with countless times elsewhere. It is mostly harmless though.
Robert Jastrow questions the significance of a beginning
No comment.
Sir Roger Penrose questions the bridge from quantum to classical and the physics of consciousness
Well, you know I have a problem with this guy. What you don't know is that I did discuss the specific issues with him many years ago that I've raised before. At that time the ideas were conjecture, but have since been proven correct. He nonetheless refuses to acknowledge this fact and continues to wallow in his ideological rut. The rest of the field has moved on without him. He is not generally considered credible in the field you mention above (and I have many personal specific reasons to question his credibility), but he is still a credible physicist in his field of expertise.
Max Tegmark questions what is all that there is
No comment. He's fine with me.
Sir Karl Popper questions what is science
I view Popper as engaging in entertaining mental masturbation, but I'm not sure that he is particularly relevant. Popper is harmless though, and I don't have any problem with him waxing eloquent about all manners of things and sounding less profound (to me) than he actually is. I put him in the pop-sci category.
So in short: Most of these guys are okay and get a pass by me. However, a couple have expertise in areas that could be argued to be tangential to the real issue and therefore not relevant even though technically correct, and couple are correct in a narrow scope but are routinely applied in a broader scope than is warranted (for this I blame the people misapplying it, not the guy himself). So a few of the people on the list don't real have a meaningful place in the discussion even though I don't have an issue with them.
And a couple (like Yockey) have zero credibility as far as I'm concerned, though your list is mostly okay with me.
Does this help you?
I think that "selection as causation" is the central concept invented by Darwin. The details have increased dramatically in number and complexity over the years, but the central insight remains.
With regard to the other questions you raise, IMHO, Hawking evidences an end justifies the means motive. He cannot entertain the possibility of an external cause and thus tortures the Big Bang with imaginary time to avoid the meaning. He reveals the motive here:
:^)
Not exactly, or at least not in the same sense. Selection does not attempt to falsify or deny what came before. What I am getting at is there is an aspect of the future that is unknowable. When humans design something, they are projecting something into the future, asserting that this object will behave thusly. This seems pretty successful when implemented in glass and steel, but we do not have the resources to predict the viability of a living system, particularly in competition with other systems, and particularly in the whole unpredictable ecosystem.
Life works around this dilemma by introducing "random" variation. The success of any given variation is determined by the future, by selection, not by design.
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