Wednesday, November 22, 2006

Kids: it’s not only about Bunsen burners

High school science class was so boring! Remember all those endless experiments involving Bunsen burners and electric light bulbs? Remember all those meaningless equations that we had to cram for the end-year exams? Did we actually come away with anything useful? I think back to those years of high school and I’ve come to realise that as a student, I didn’t learn anything about science in science class.

As students we didn’t realise it, but the stuff we did at school was simply the end product of something greater: it was the product of a method of thinking that involves aspects of reason, hypothesis testing and critical thought. Although we learnt a lot about what science can do, we learnt very little about scientific thought. I wish that we did fewer experiments at school, and learnt more about developing a scientific mindset, a mindset that places emphasis on the pursuit of truth rather than the proclamation of truth.

The historian Richard Carrier writes an interesting article in which he describes a scientific mindset as being:

“. . . a system of beliefs that produces advances in knowledge, including a belief that public evidence and verifiable reason trump all authority in explaining what is and can be, that persuasion by appeal to observable evidence and sound logic is the only valid means of gaining consensus about the truths of this world, that this requires embracing everyone's intellectual freedom to accept, reject, or propose any idea they please, and that it is valuable and good to devote your life in this way to the pursuit of progress in understanding any aspect of nature or existence.” (emphasis added).

Let’s focus on the value of intellectual freedom. All religions have, at one time or another, suppressed intellectual freedom in favour of dogma. Intellectual freedom, the free market-place of ideas and thought, implies that everyone can make up their own minds regarding nature, religion and personal meaning. It is a threat to those institutions, such as religious fundamentalism, that aim to control the thoughts and beliefs of people.

Scientific progress can only be effective if it can operate within the context of intellectual freedom, if it is free to propose and test ideas that might seem blasphemous or heretical to the current status quo. Even now, religious fundamentalism is fighting against current advances and ideas in science. Biological evolution is but one example: the non-scientific approaches that creationists use – such as appealing to faulty arguments and trying to ban the teaching of evolution in schools – is cause for concern. Each time a school board in the United States votes against teaching evolution for religious reasons, I get nightmarish visions of what such actions can lead to if left to spiral out of control: another Dark Age of suppression, extreme censorship and persecution of non-believers?

We have much to learn from the Dark Ages, from what religion can do if it is given too much power. I think science class can be much more effective if it can teach children about the dangers of dogma, fundamentalism, and an unquestioning devotion to one type of paradigm. Reduce the number of textbook experiments; teach a little more about critical thinking and scientific thought. That’s my humble opinion.

14 comments:

Lui said...

At the risk of sounding conspiracy-theory minded about it, is it possible that the reason there is so little emphasis on developing a scientific mindset is because those in power feel threatened by the people becoming too clever? If we could all think in a rational, scientific manner, we'd be far more bullshit-resistant; the threshold of our bullshit detectors has been set too high by the totality of the propaganda and indoctrination from those institutions that have an interest in keeping certain things from us; if our bullshit-detectors were more sensitive, governments wouldn't be able to lie to us as easily as they do, corporations wouldn't be able to turn everything into a commodity and have us overlook their crimes, and religious leaders wouldn't be able to sell their claptrap to nearly the extent that they've been doing for so long. Governments want us to be patriotic and “good citizens”, corporations want us to become indifferent, nihilistic consumer robots, and religious leaders want to maintain pre-scientific belief systems in the face of progress and reason. Knowledge is power, and denying knowledge to others is also power.

Anyway, just a thought.

beepbeepitsme said...

I agree that if you want to teach science, it is recommended to teach the scientific process. Without that, it is just a case of "monkey see and monkey do."

RE lui:

I agree with you on the BS detector, mine is set to full throttle.

r10b said...

I think science class can be much more effective if it can teach children about the dangers of dogma, fundamentalism, and an unquestioning devotion to one type of paradigm.

I think those who would like to teach Intelligent Design in public schools would agree with you wholeheartedly.

If there is (and there certainly is) factual, observable, scientifically-based, evidence against some of the elements of Darwinian evolutionary theory, then it should be fine with you that such evidence be discussed in schools. If not, then dogma has won the day.

Bottom-line: I agree completely with your premise, but I think it would have a negative effect on the status of the ideology of an unguided naturalistic theory of origins...in my humble opinion.

Lui said...

Intelligent Design isn't science; it's re-hashed creationism using the language of science in the furtherance of religion. It basically amounts to saying: "I can't imagine how this structure could have evolved. Therefore, it must have been designed by God." By all means, teach kids about the difficulties in Darwin's theory (if there are any) but don't automatically presume that Intelligent Design is a real alternative (it's worth noting three things here: just because something claims to be an alternative doesn't mean it's a scientific alternative, and aligning with the beliefs of the scientifically ignorant doesn't change that; just because something is in fact an alternative doesn't mean we should presume it to be the default choice in explaining outstanding phenomena unless it gives us some reason to take it seriously with positive evidence of its own; and finally, some of the claims made by ID have since been debunked in the scientific literature, such as claims about "irreducible complexity". Whether they continue to be used as arguments by ID advocates is irrelevant to their scientific status).
Darwinian evolution by cumulative, non-random natural selection is not an ideology but a scientific theory like electromagnetism or the weak nuclear force. It is supported by overlapping, converging data from disparate fields in biology and is accepted because by the overwhelming majority of the scientific community because of the degree to which these pieces of data are what we would expect to be the case if evolution is true. If anything, your arguments it speaks more against ID (which can be more properly called an ideology) than it does against Darwinian evolution.
I'd be in favour of teaching ID in a philosophy course, or a course about society and culture, but not in a science course, and definitely not in a secular, public school (or indeed, not even in a private, religious school; children have the right to be protected form their parents’ ignorance). Perhaps, if it does end up being taught in public schools, scientists should demand equal time in church, where they can teach population genetics and natural selection alongside Genesis. All in the name of fairness, of course, for the Biblical account is "just a theory".

r10b said...

...your arguments it speaks more against ID...than it does against Darwinian evolution

My so-called argument does not speak for or against either, but about what Kevin wrote — objectively addressing the facts free from ideological bias.

My position (not argument) is that those who believe that the God of the Bible created the universe and all life in it in some fashion have nothing to fear from such a policy. (Young-earthers excepted.)

This thread is not about the creation/evolution debate.

Lui said...

"objectively addressing the facts free from ideological bias."

Sure, I agree with that, as should everyone who claims to have the interests of science at heart, but if only it were so for ID advocates. Addressing the facts free from ideological basis is really just a sneaky way of trying to sound fair and open-minded, just wanting to have a fair-go. "In the interests of fairness, let's here both sides of the story, and let the students make up their own minds." It sounds so noble, until you get to its fundamentalist core. The problem is, ID isn't about looking at facts without ideological bias, it's about interpreting them THROUGH ideological bias and coming to the presupposition that, just because someone can't imagine how something could have evolved, that "therefore" it must have been designed by an Intelligent Designer (God, of course. IDists might claim that the designer could also have been an extraterrestrial, but let's be serious here). ID claims to be scientific, but upon closer scrutiny its claims have broken down. It's a more sophisticated version of creationism, usually making do without the obviously ridiculous claims of young Earth creationism (at least the more extreme claims).

Darwinian evolutionary theory isn't "ideology", and the overwhelming majority of scientists don't accept it based upon ideological prejudice. Many of them are themselves theists. They accept it because it fits the facts and because what we find in the natural world is what we would expect to be the case if it's true. Evolution is what we've arrived at in regarding as the best theory precisely because of freedom from ideological bias. It's really disingenuous of IDists to try to make themselves look like the good guys in this.

r10b said...

I agree that think IDers are being coy about their ultimate objectives.

On the other hand even Eugenie Scott has criticized Richard Dawkins for often "erasing the line between science and philosophy." And he's not the only one.

Darwinian evolution by cumulative, non-random natural selection is not an ideology but a scientific theory like electromagnetism or the weak nuclear force.

The published statements that follow show three things:

a) Your understanding of the theory is unconventional.

b) There is a good bit of ideology in the mix when the theory is presented in public schools.

c) Textbooks on the theory make expansive philosophical pronouncements that are not found in books on electromagnetism or weak nuclear force.

--

“Evolution works without either plan or purpose — Evolution is random and undirected.”
--(Biology, by Kenneth R. Miller & Joseph S. Levine (1st ed., Prentice Hall, 1991), pg. 658; (3rd ed., Prentice Hall, 1995), pg. 658; (4th ed., Prentice Hall, 1998), pg. 658; emphasis in original.)

"Once pointed in a certain direction, a line of evolution survives only if the cosmic dice continues to roll in its favor. Just by chance, a wonderful diversity of life has developed during the billions of years in which organisms have been evolving on earth.”
--(Biology by Burton S. Guttman (1st ed., McGraw Hill, 1999), pgs. 36-37.)

“By coupling undirected, purposeless variation to the blind, uncaring process of natural selection, Darwin made theological or spiritual explanations of the life processes superfluous.”
--(Evolutionary Biology, by Douglas J. Futuyma (3rd ed., Sinauer Associates Inc., 1998), p. 5.)

“Darwin knew that accepting his theory required believing in philosophical materialism, the conviction that matter is the stuff of all existence and that all mental and spiritual phenomena are its by-products. Darwinian evolution was not only purposeless but also heartless–a process in which the rigors of nature ruthlessly eliminate the unfit. Suddenly, humanity was reduced to just one more species in a world that cared nothing for us. The great human mind was no more than a mass of evolving neurons. Worst of all, there was no divine plan to guide us.”
--(Biology: Discovering Life by Joseph S. Levine & Kenneth R. Miller (1st ed., D.C. Heath and Co., 1992), pg. 152; (2nd ed.. D.C. Heath and Co., 1994), p. 161.)

"Nevertheless, faith in religious dogma has been eroded by natural explanations of its mysteries, by a deep understanding of the sources of human emotional needs, and by the recognition that ethics and morality can change among different societies and that acceptance of such values need not depend on religion.”
--(Evolution by Monroe, W. Strickberger (3rd ed., Jones & Bartlett, 2000), pg. 70-71)

--

No ideology there! It seems that talking about God in science class is ok as long as you're denying His existence.

Lui said...

I don't agree that my understanding of evolution is unconventional, because the only way complexity can arise is indeed though cumulative, non-random natural selection, and this has been expressed clearly by many workers in the field. It's true that Darwinian evolution is devoid of plan or purpose; this is no problem for the theory itself, because plan and purpose are not prerequisites for the evolution of complexity, but rather reflect our own anthropocentric prejudices. The large scale trends in evolution may well be due to chance factors like mass extinction events more than they are due to events at the inter-population level; it's perfectly reasonable to suppose that had the K-T event not wiped out the dinosaurs, that we wouldn't be here and that another species of intelligent life might be pondering these very issues in our "place". But the within-population processes that build up complex structures are anything but random. There is probably a good dose of chance in the shaping of the tree of life, but this is different to saying that evolution is fundamentally a chance process. It's more accurate to say that it's a systematic process that works on contingencies.

The third quotation actually says nothing controversial, or at least it shouldn't be controversial when you really think about it. Where once we thought of life as having come about by the divine hand of a creator, we now have no need for that notion because science offers a more parsimonious, elegant solution. There may well be other reasons to believe in god, but biological complexity and diversity are no longer among them - UNLESS evidence can be shown to the contrary. Invoking God in biology is indeed superfluous, but this is no fault of Darwinian theory. It's only seen as a fault by those who presume from the outset that biology SHOULD make reference to God, but the reasons for doing so almost invariably turn out to be religious, non-scientific reasons.

As to the fourth quote, I don't know if I would agree that accepting evolution necessarily leads to accepting philosophical materialism in its entirety, but it's definitely consistent with it and again, is devoid of superfluous concepts for which there is no evidence. The forces that gave rise to us - AS BEST AS WE CAN TELL THROUGH OUR SCIENCE - are indeed heartless, cold and indifferent to suffering. Again, this doesn't in fact mean that there is no God, but it gives us no reason to invoke God – let alone in a science classroom – in the first place.

The fifth quotation is also uncontroversial, because the author is simply making a statement about the how natural explanations of previously mysterious phenomena have eroded religious faith. The author isn't saying that this is a good thing, only that it's something that's occurred, maybe something that's inevitable.

The science curriculum should be under no obligation to restore people's pre-Darwinian comforts. Science should be presented without emotion, for it makes no claims about how we should live our lives or how we should derive meaning. It tells us only about how the universe operates. There’s no imperative to "deny Him" simply because there hasn't been any don't need to invoke him in the first place, and affirming him is something that needs to be justified on purely scientific grounds. So far, such grounds have been virtually absent.

In the words of Richard Dawkins: "Just because two positions are being argued for with equal rigour doesn't mean that the truth lies somewhere in between the two. There is such a thing as just being wrong."

r10b said...

It's more accurate to say that [evolution is] a systematic process that works on contingencies.

Yet all the definitions of Darwinist, and especially neo-Darwinist, evolution in textbooks that I quoted (and all others I have ever seen) contradict you. As far as I know, neo-Darwinism differs from Darwinism in large measure due to nD's insistence on randomness in genetic mutation. Show me a published definition of D or nD evolution that matches yours.

The 3rd quote: "...Darwin made theological or spiritual explanations of the life processes superfluous." By speculation only. Again, as far as I know, it has yet to be show that inaminate matter can give rise to life, which is the most basic point of the ideology (as apposed to the scientific theory). Thus such a statement if ideological.

The 4th quote: "Darwin knew that accepting his theory required believing in philosophical materialism, the conviction that matter is the stuff of all existence and that all mental and spiritual phenomena are its by-products...Worst of all, there was no divine plan to guide us." You properly disagree with the "required believing in philosophical materialism," but your conditional "as far as science can tell" is noticably absent from the published text. Therefore it at least smacks of ideology. I admit that this is not a tremendously strong case for an ideological perspective given the context.

The 5th quote: It's not the eroding of religion part that is ideological, that is observation. It this part, "a deep understanding of the sources of human emotional needs, and by the recognition that ethics and morality can change among different societies and that acceptance of such values need not depend on religion" that goes beyond that bounds of biology since biology only can speculate on the sources of human emotional needs, ethics, and morality.

Science should be presented without emotion, for it makes no claims about how we should live our lives or how we should derive meaning.

I agree, but as evidenced by the quotes above and by much of what I've read of Dawkins and others, they certainly do make such claims.

"Religion has been bolstered by paternalistic social systems in which individuals depend on the beneficiences of those more powerful than they are, as well as the comforting idea that humanity was created in the image of a god to rule over the world and its creatures."
--(Evolution by Monroe, W. Strickberger (3rd ed., Jones & Bartlett, 2000), pg. 70-71)

Now the text above may or may not be true, but please explain to me why such a quote rightly belongs in a biology textbook. When the biologists start to make (what they expect are) authoritive statements on religion or ethics, or spiritual matters, then they have strayed out of their science and into what we both seem to agree is forbidden territory. Yet it happens with regularity.

Kevin's original point is that we should guard against religion invading the science class. It seems religion already has and that a purging is in order.

affirming him is something that needs to be justified on purely scientific grounds

This means that God in His totality must be comprehensively contained within the limits of science. Those limits are things that can be in empirically observed and made predictable. Science, therefore, is not capable of affirming Him to any degree beyond what His has revealed. He is revealed in nature (design, causality) and within us (morality, desire).

However, I accept the truth of these words from Pascal:

I admire the boldness with [some people] undertake to speak of God. In addressing their argument to [unbelievers], their first chapter is to prove Divinity from the works of nature....[This serves only] to give them ground for believing that the proofs of our religion are very weak. And I see by reason and experience that nothing is more calculated to arouse their contempt...It is an astounding fact that no canonical writer has ever made use of nature to prove God...David, Solomon, etc., have never said, "There is no void, therefore there is a God." They must have had more knowledge than the most learned people who came after them, and who have all made use of this argument. This is worthy of attention.
--(Pensees, IV, 242, 243)

I have really enjoyed this discussion with you, lui. Most times these things degrade quickly and I dread sticking my nose back into the melee. Thanks for keeping things positive. You made some good points and I look forward to more such conversations.

Lui said...

Yes, the mutations themselves are random, but their preservation due to selection is emphatically not. Selection tends to preserve mutations that confer some advantage on an organism, and weeds out the deleterious mutations. It's subtler than that, but basically that's the gist.

"Show me a published definition of D or nD evolution that matches yours. "

Any publication by Dawkins, Maynard Smith, or indeed any evolutionary biologist, dealing with biological complexity, will attest to this. Individual scientists might disagree in the details, and might give different emphasis to other processes in evolution when it comes to explaining overall trends in evolution, but no sane biologist will tell you that selection (as opposed to mutation, which is random) is a haphazard process. Darwin himself said as much in "The Origin of Species". It goes against the very DEFINITION of selection to say otherwise. From Dawkins: "It is grindingly, creakingly, crashingly obvious that if Darwinism was really a theory of chance, it could not work."

Also from Dawkins, a neo-Darwinist if ever there was one: "Life results from the non-random survival of randomly varying replicators." In other words, selection acts on the variation produced by mutation and sexual recombination. Such a view is expounded with great clarity in his “Climbing Mount Improbable” and “The Blind Watchmaker” books, where he deals at length with adaptations like eyes and echolocation.

The very reason that complexity is slow (by our time-scale) to arise is precisely because the structures in question are statistically highly unlikely to come about by random chance alone. By necessity, a NON-random factor is required. Otherwise it's the same as the lottery, except much worse, because the structures in question really are too fantastically improbable by chance alone. This really is uncontroversial and fully mainstream. Where people get confused first is in supposing that evolution is all about chance; the next conceptual hurdle lies in acknowledging that evolution is unguided and unconscious, yet capable of building up structures which LOOK as though they were designed. This really messes with peoples' heads, and seems utterly counterintuitive. But looks can be deceptive, and the solution is not only elegant, but is also the only serious scientific candidate. There is an enormous amount of evidence to back it up. Once you've climbed the conceptual hurdle, it becomes almost obvious, even ridiculously so. Evolution is very simple in principle (though can be very complicated in the details).

"...biology only can speculate on the sources of human emotional needs, ethics, and morality"

Enormous strides have been made in the study of the brain, and these are far from "mere speculations." I have been given no compelling reason to suppose that any other field comes close to biology in this regard. Religion CLAIMS to give us insights, but what REASONS has it given us to take its claims seriously? I'm not saying that, even if the entire basis of human morality and consciousness is derived from physical interactions, that it means that there is no God. But it seems irrational to try to strong-arm science by claiming that it can provide only speculations, and presuming that we should give religion the benefit of the doubt just because it's traditionally provided supposed answers to these questions. Religion itself, you may be aghast to hear, is now being studied scientifically, and, somewhat ironically, with the tools of evolutionary psychology. It may be part of the picture, but it seems that so far religion has only provided claims.

"Now the text above may or may not be true, but please explain to me why such a quote rightly belongs in a biology textbook. When the biologists start to make (what they expect are) authoritive statements on religion or ethics, or spiritual matters, then they have strayed out of their science and into what we both seem to agree is forbidden territory. Yet it happens with regularity."

I don't know the context of that passage. For all I know, that author may well be an authority on religion. Or it could be that the author was attempting to provide an evolutionary framework with which to study religion, and was highlighting the factors that have contributed to its ascendance in human society. Perhaps it was inappropriate in any case, but such arguments are not needed to bolster the overall picture of evolutionary biology, perhaps only to illustrate how profoundly it has revolutionised our view of humanity and our place in the universe. The evidence for the evolution of the human species is as strong as you can get. I don’t defend the author’s decision to include those words in a biology textbook, (even though I agree with them) but I would need to know why he chose to do so. It’s clear to me that evolutionary biology speaks for itself, and needs no broad, sociological words of encouragement to bolster it.

"Science, therefore, is not capable of affirming Him to any degree beyond what His has revealed. He is revealed in nature (design, causality) and within us (morality, desire)."

But if it can be shown that he isn't necessary, then what are we left with other than just WANTING him to be there? He might be there or he might not, but if science gives us no grounds to think that he has even revealed himself to us, then all the worse for him! Science shouldn't be in the business of making concessions to people’s beliefs if those beliefs actually have nothing to do with science in the first place. By all means pursue them elsewhere, but the science classroom is not the place for that. It should be noted that many Christians believe that evolution was God's method of producing us; design, in that light, isn't the only solution (in fact some see Intelligent Design and creationism as sacrilegious because they see it as cheapening God, who had to intervene in his own creation because the laws of physics he set up weren't sufficient to get the job done; Darwin, in this view, becomes God’s spokesman).

Thank you for your thoughts, too. It's been enjoyable responding to and thinking about them.

r10b said...

Yes, of course the natural selection function is not random; but the mutation that gives the advantage supposedly is, therefore environment (the threat) has no input into the mutation, but it causes the mutation to be passed on thereby eventually becoming common in the population.

In my mind this does nothing to make Darwinism more probable. Survival still depends on random chance mutation (before non-random natural selection can even get going), and that chance is astronomically, even preposterously slim.

But if it can be shown that [God] isn't necessary...

I disagree that the science has shown (proven) that Divine intervention isn't necessary. That is placing a philosophical POV on the data.

Wanting him to be there is philosophical, not scientific evidence, but evidence nonetheless.

What about not wanting Him to be there? Is that any more excusable? Read on...

"The biggest problem with the Big Bang theory of the orgin of the Universe is philosophical—perhaps even theological—what was there before the bang? This problem alone was sufficient to give a great initial impetus to the Steady State theory; but with that theory now sadly in conflict with the observations, the best way round this initial difficulty is provided by a model in which the universe expands from a singularity, collapses back again, and repeats the cycle indefinitely."

This quote is from physicist John Gribbin, published in 1976 in the journal Nature and I just came across it by chance :)...

Two things to notice here:

1) He admits that the philosophical/theological "problems" gave rise to the Steady State theory in the first place, not an unbiased scientfic method.

And now that observations have discredited that theory...

2) He proposes new theory that is based solely on discounting the philosophical/theological implications of the Big Bang against the observed (and tested and verified) facts.

This is exactly the type of thing that Kevin rightly argues against.

The idea that Christians or other Theists are the only ones who distort science, the scientific method, or the teaching of science, in order to conform it to their ideology is itself a biased assumption.

--

We probably have nowhere to go but on into a debate over evolution itself and, if you don't mind, I'd rather not open that can of worms at this time.

Thanks again for your thoughtful and helpful feedback. I hope everything is going well for you Down Under.

r10b said...

Also from Kevin's original post...

All religions have, at one time or another, suppressed intellectual freedom in favour of dogma.

Intellectual freedom has been opposed from all quarters, depending on the philosophical/theological positions that freedom threatened. (See my post above.)

But look into who resisted Einstein's Theory of Relativity. Was it the Church? No. It was those ideologically opposed to a Creator. Even Einstein himself initially resisted but eventually acknowledged "the neccesity for a beginning" and "the presence of a superior reasoning power." But he let the facts speak. To Einstein they spoke of a Creator (though He denied a personal God on philosophical grounds, the omnipotence/free will dilemma.)

(Quotes from Einstein's Out of My Later Years)

Not everbody had their ears open.

"Philosophically, the notion of a beginning of the present order is repugnant...I would like to find a genuine loophole.

"We [must] allow evolution an infinite time to get started."

-Cosmologist Sir Arthur Eddington (from two scientific journals published in the 1930's)

Lui said...

"In my mind this does nothing to make Darwinism more probable. Survival still depends on random chance mutation (before non-random natural selection can even get going), and that chance is astronomically, even preposterously slim."

Actually, it isn't, and virtually every geneticist and developmental biologist would disagree with you. The fact that mutations are random is no problem for the notion that they're essential to evolution. All that matters is that a non-random function preserves those mutations that happen to confer some sort of advantage on their carriers. Most mutations will be either neutral or deleterious, but some will be beneficent. It's those beneficent ones that fuel the process. It's the CONSEQUENCE of the mutation that counts, not where it came from. It's also not true that they are so rare that the right mutations would never show up; evolution is a population phenomenon, not an individual one. The odds that any particular animal will produce the right mutation are slim, but the odds that some animal from the entire population will do so isn't.
Darwinian evolution is not seriously in doubt. If anything, the new evidence from genetics only reinforces it, and allows us to study it at an unparalleled level of sophistication. Founder mutations have been used by scientists to track past human migrations, and even more fascinating are "fossil genes", genes that have lost their function during the course of evolution and are in the process of "decay". According to Sean B. Carroll, about 900 fossil genes have been found in humans, and 70 of those have resided in our genomes since the split with the common ancestor with chimpanzees. As you go back down the evolutionary tree, you find less and less fossil genes in common between us and that organism, as would be expected. Fossil genes that are clearly homologues of function genes for smell receptors have been found in dolphins, which barely have a sense of smell. By studying the fossil genes of modern genomes and comparing those sequences with functional homologues, we can learn about the types of environments that the ancestors of these animals once lived.
In addition, developmental “tool kit” genes such as Hox genes are the focus of current research into the evolution of body plans. These are genes that are activated at different times of the organisms’ development and in different regions of the embryo. They produce proteins that switch on other genes. It’s like a computer program instantiating a function by calling it, then returning control to the calling subroutine. By tinkering with these Hox genes, evolution has produced all manner of forms. Fruit flies and human beings have Hox genes that are clearly homologues to one another, and are clearly derived from a common ancestor. In fact, scientists took out a Hox gene for eye development from a mouse and transplanted it into a fly. It worked; this, among many other pieces of similar evidence, shows that the program for building a complex multicellular organism is ancient, and that all modern multicellular animals are derived from a common ancestor that possessed Hox genes. Humans have four clusters, flies have one. Gene duplications of this sort are thought to have been an important factor in the evolution of complexity.

By altering when and where switches are turned on and off, natural selection can lead to the specialisation of previously homogenous limbs, the elongation of body parts by repeating the number of segments they contain, and the building up of new structures from prior structures. We can attach special marker enzymes to genes so that we can watch when they are being expressed in different animals, and seeing what proteins are produced and if they are similar across different groups of animals. Sometimes we find that proteins that are essential to the development of a complex structure are found in simpler organisms, and by looking at the fossil record and differences in the genes' switch sequences, we can infer a lot about the likely pathways that evolution took to produce the "higher animals".

As to the Big Bang, it may well be that the "reasons" for its coming about will forever remain mysterious. But consider what introducing God would do: instead of resolving the dilemma, you're magnifying it a trillion-fold. Where is God supposed to come from? God is a being who can supposedly hear prayers, intervene in human affairs and engineer life. Such an entity needs an explanation in its own right; such complex things don't come into the universe fully formed, they have to be the product of a long process of cumulative chance. I'm with Dawkins on this one: whenever or if ever we come to the "ultimate explanation", it will be a simple one, not a complex one.

Actually, to be perfectly honest, I have been grappling with this issue for some time now. I've wondered what it is that means that there is "something instead of nothing". I wrought an e-mail message to Professor Edward L. Wright, an astronomer at UCLA. I asked him about these things, and his response was that my question was more of a metaphysical one than a physics one, but he also added that quantum mechanics allows for matter to come out into existence from nothing. String theory also predicts parallel universes, most of which would not be capable of harbouring life. Even without the possibility of parallel universes or a recurring Big Bangs, the anthropic principle comes (partially) to our rescue.

I find the notion of the Big Bang quite perplexing, but upon further reflection I see that a supernatural explanation shouldn't be immune to the same type of scrutiny as a naturalistic one. And invoking a supernatural explanation only compounds the problem instead of coming close to resolving it. To be sure, the problem might never be resolved anyway, but God is a massive injection of the very thing we're trying to explain in the first place: complexity.

Lui said...

Sorry, the link for Sean Carroll's website is seanbcarroll.com/