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2012年7月26日 星期四

The Limits of Ignorance 5

Cont'd

I've been talking about the controversy surrounding the teaching of ID in American high schools and how it failed to get the American federal court's approval  for doing so. What do ID advocates have against Darwin's evolutionary theory? Behe's main complaint is that modern evolutionary science could not give a "detailed account of how the cilium or vision or blood clotting or any complex biochemical process might have developed in a Darwinian fashion" (DBB 187). He argues that if something is not put together gradually, then it must have been put together quickly or even suddenly and that if adding individual pieces does not continuously improve the function of a system, then multiple pieces would have to be added together. He then discusses two ways of rapidly assembling a complex system proposed by modern biology and how they are unsatisfactory.

The first alternative to gradualism was championed by Lynn Margulis who proposes advancement by co-operation and symbiosis whereby organisms help one another and accomplish together what they could not accomplish separately. A eukaryotic cells is full of complex "molecular machines" tidily separated into many discrete compartments the biggest of which is the nucleus, with one fifth of the volume of the typical cell containing about 2000 smaller compartments called "mitochondria" each of which contains machinery needed to capture the energy of food consumed and to store such energy in a chemically stable but readily available way. Such mitochondria uses a flow of acid to power its machines which shuttles electrons among half a dozen of carriers and such operations require an exquisitely delicate interactions between many components. Margulis suggests that at one time on the ancient earth, a larger cell would "swallow" a bacterial cell, roughly the size of the "mitochondria" but did not digest it so that we have one smaller cell living within a larger cell. The smaller cell would receive nutrients from the larger host cell and in return would pass on to its host some of the chemical energy it made and when the larger host cell reproduced, the smaller one did too and the smaller cell and its descendants would continue to reside in body of the larger host cell and over time, the symbiotic cell would lose many of the systems that free-living cells need e.g a mouth and specialized more and more in providing energy for its host and eventually it became a mitochondria. Behe asks: "can symbiosis explain the origin of complex biochemical systems?" He says that it cannot because the essence of the symbiosis is the joining of two previously separate cells or two separate systems, both of which are already functioning. He complains that neither Margulis nor her followers gave any "detailed explanation" of "how the pre-existing cells orginated" (DBB 189). To him, symbiosis may help to explain the "development" of life on earth but not the "ultimate origins" of complex systems. (DBB 189)

The second alternative to gradualism is "complexity theory" (chaos theory), one championed by Stuart Kauffman. According to this theory, a large number of interacting components would "spontaneously organize themselves into ordered systems and sometimes there are several patterns available to the complex system and "perturbations" of the system can cause it to switch from one pattern to the other. Kauffman proposed that chemicals in the pre-biotic soup in the beginning of the earth's history organized themselves into complex metabolic pathways and further proposed that the switch between cell "types"( like how a fertilized egg goes on to make liver cells, skin cells etc) is a "perturbation" of a complex system and results from the spontaneous self-organization he supposed. Kauffman compares the situation to what happens when very complex computer images can be produced by introducing "random changes" to some originally very very simple computer programs but repeated over a long period of time. Kauffman describes it thus: "most mutations have small consequences because of the system's [change-resisting] nature. A few mutations, however, cause large cascades of change. Poised systems will therefore typically adapt to a changing environment gradually, but if necessary, they can occasionally change rapidly. These properties are observed in organisms."  (Antichaos and Adaptation Scientific American August 1991 82) (DBB190) ie. small changes in a computer program may cause large changes in the computer output, something now popularly called "butterfly effect". By analogy, Kauffman proposed that small changes in the relevant DNA can produce large co-ordinated biological changes. Behe complains that Kauffman did not go into a lab and test if his hypothesis is right by doing experiments to see if "self-sustaining metabolic pathways spontaneously organize themselves." (DBB 190). Behe asks, even if we were to "assume" that Kauffman is right, "can this explain the origin of complex biochemical systems?". No. he says, because "no eukaryotic cell can turn on pre-existing genes and suddenly make a bacterial flagellum because no pre-existing proteins in the cell interact that way. The only way a cell could make a flagellum is if the structure were already coded for in its DNA.". In short, he is complaining that even if Kauffman were right, Kauffman could not explain the ultimate "origin" of life. All Kauffman could do was to explain how "life" could have "developed" after it started! This is, I think, a fair criticism.

To me, Behe's arguments against both Margulis and Kauffman merely rehearse the familiar philosophic argument about "infinite regression": even if we succeed in explaining an effect E, by giving cause C1, we can always ask what is " cause" of "cause C1" and suppose that further cause is "cause C2", we can go on to ask what is the cause of "cause C2" and so on ad infinitum. If he thinks this is unacceptable and unsatisfactory, then I can apply the same logic that he is using to what I think he is driving at and supposing he were to say that the ultimate cause of life is the "intelligent designer" ie. God, I can following his logic, pose the question "what is the cause of God" or "who made God? ". The theological answer, based on nothing but "doctrine", is that God is the ultimate cause, the first cause, the cause of itself/himself/herself but is the cause of every thing else in the universe. This is a metaphysical answer, based on nothing but belief, not on logic or reason nor on what non-Christians, non-Muslim, non Jewish faith followers, would regard as "evidence".  It is certainly not a "scientific" answer. Science does not concern itself with metaphysical questions and science operates on the "assumption" that all "natural" phenomena have "natural" causes, not "supernatural" causes, a cause of complaint by another ID advocate Phillips E Johnson, whom I shall deal with later..

What we are dealing with in evolution theory is a "scientific" theory, not a "metaphysical" or "religious" theory of existence. We are dealing with the "evolution" of life, not the ultimate "origin" of life, including, in particular,  something of interest to the followers of Abrahamic religions (Judaism, Islam, Christianity, who worship the same God), the origin of "human beings", part of what Christians call "special creation": whether human beings started "human" life as a result of "evolution" from apes or whether he was created in more or less the form that he is from the very beginning. But the advocates of ID have a secret agenda: that all life began with creation by their Christian God as the "creator" and "lord" of the universe.

The attack on the theory of evolution by Christians did not start only in the 20th century. It started soon after Darwin proposed it in the 19th century. There was a famous debate  between Aldous Huxley and Bishop Wilberforce in which the latter asked rhetorically whether Huxley was descended from apes on his paternal or his maternal side! The promotion of the ID thesis was the work of the Discovery institute, founded in 1991 by conservative politician  and its president Bruce Chapman, whose public relations arm is the Creation Research Society's Centre for the Renewal of Science and Culture (CRSC) founded in 1996 ( renamed Centre for Science and Culture ("CSC") in August, 2002, dropping the word "Renewal") , and Chapman stated very clearly what the goals of the CRSC were in a letter to his subordinates: " To defeat scientific materialism and its destructive moral, cultural and political legacies. To replace materialistic explanations with the theistic understanding that nature and human beings are created by God...Accordingly our Center for the Renewal of Science and Culture seeks to show that science supports the concept of design and meaning in the universe--and that design points to a knowable moral order" (Chapman B 1998 Letter from the President, Seattle, Discovery Institute quoted in SCC 65). It quickly replaced the FTE as the hub of ID activities. Its real religious and political motives cannot have been stated more clearly!

(To be cont'd)

4 則留言:

  1. 吾生也有涯、而知也無涯。pursuit of knowledge is dangerous. I would rather be a agnostic.
    [版主回覆07/26/2012 23:00:39]Jesus said, unless a man shall die, he shall not live again! We must be dead to our old self so that the new Adam may be born!
    [pinkpanther501101回覆07/26/2012 21:28:22]The question at the end of your comment is like asking a dead person whether he wants to be born again, to live a new life and experience the joys and sorrows of the human condition anew. The teachings of the Buddha and the Bible do have something in common.
    [pinkpanther501101回覆07/26/2012 20:50:10]I think of one interesting thing: unconscious ie we know things we do not know we know. I read that our unconscious might make us do things like typing the wrong key of a type writer in order to prevent us from remember important things. I have personal experience of the power of the unconscious.
    [版主回覆07/26/2012 17:41:22]Jean Jacques Rousseau said "man is born free, but everywhere he is in chains".A century and half later, his fellow countryman Jean Paul Sartre said, we are "condemned to be free": we are free despite ourselves. But freedom is a painful duty and may weigh upon our shoulders like a hundredweight. We are free to know. But we are also free not to know. The Buddha taught us that we must always live with full awareness of the true conditions of our life. Was it Socrates who said that the unreflected life is not worth living? To know or not to know, that is the question. Not only is the pursuit of knowledge dangerous. It is even more dangerous to know just a little. Certainly, we may choose to close our eyes to things around us. The Bible taught us the price of knowledge: Adam and Eve were driven from the Paradise of Eden because they ate of the tree of knowledge. Shall we be ignorant and live happily in the bliss of the paradise of the the ignorant or shall we open our eyes and see the sorrows of the human condition as well as its joys?

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  2. He who knows does not speak. He who speaks does not know.
    [版主回覆07/26/2012 23:04:19]That is LaoTzu speaking.

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  3. 有冇去書展呀 Elzorro
    [版主回覆07/26/2012 23:22:58]Sure, in spirit!

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  4. “To defeat scientific materialism and its destructive moral, cultural and political legacies.” How dogmatic a statement, leaving no room for rational discussion!
    [版主回覆07/28/2012 12:42:12]It is sometimes said that the priests and pastors expect us to deposit our brains at the doorsteps to the church!

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