What makes us change our minds?

(I am taking a short vacation from new blog posts. I will begin posting new entries again, on August 27, 2007. Until then, I will repost some early ones. Today’s one is from March 28, 2005, edited and updated.)

In an earlier post, I described the three kinds of challenges teachers face. Today I want to discuss how teachers might deal with each case.

On the surface, it might seem that the first kind of challenge (where students do not have much prior experience (either explicitly or implicitly) with the material being taught and don’t have strong feelings about it either way) is the easiest one. After all, if students have no strong beliefs or prior knowledge about what is being taught, then they should be able to accept the new knowledge more easily.

That is true, but the ease of acceptance also has its downside. The very act of not caring means that the new knowledge goes in easily but is also liable to be forgotten easily once the course is over. In other words, it might have little lasting impact. Since the student has little prior knowledge in that area, there is little in the brain to anchor the new knowledge to. And if the student does not care about it one way or the other, then no effort will be made by the student to really connect to the material. So the student might learn this material by mostly memorizing it, reproduce it on the exams, and forget it a few weeks later.

The research on the brain indicates that lasting learning occurs when students tie new knowledge to things they already know, when they integrate it with existing material. So teachers of even highly technical topics need to find ways to connect it with students’ prior knowledge. They have to know their students, what interests them, what concerns them, what they care about. This is why good teachers tie their material in some way to stories or topics that students know and care about or may be in the news or to controversies. Such strategies tap into the existing knowledge structures in the brain (the neural networks) and connect the new material to them, so that it is more likely to ‘stick.’

The second kind of challenge is where students’ life experiences have resulted in strongly held beliefs about a particular knowledge structure, even though the student may not always be consciously aware of having such beliefs. A teacher who does not take these existing beliefs into account when designing teaching strategies is likely to be wasting her time. Because these beliefs are so strongly, but unconsciously held, they are not easily dislodged or modified.

The task for the teacher in this case is to make students aware of their existing knowledge structures and the implications of them for understanding situations. A teacher needs to create situations (say experiments or cases) and encourage students to explore the consequences of the their prior beliefs and see what happens when they are confronted by these new experiences. This has to be done repeatedly in newer and more enriched contexts so that students realize for themselves the existence and inadequacy of their prior knowledge structures and become more accepting of the new knowledge structures and theories.

In the third case, students are consciously rejecting the new ideas because they are aware that it conflicts with views they value more (for whatever reason). This is the situation with those religious people who reject evolutionary ideas because they conflict with their religious beliefs. In such cases, there is no point trying to force or browbeat them into accepting the new ideas.

Does this mean that such people’s ideas never change? Obviously not. People do change their views on matters that they may have once thought were rock-solid. In my own case, I know that I now believe things that are diametrically opposed to things that I once thought were true, and I am sure that my experience is very common.

But the interesting thing is that although I know that my views have changed, I cannot tell you when they changed or why they changed. It is not as if there was an epiphany where you slap your forehead and exclaim “How could I have been so stupid? Of course I was wrong and the new view is right!” Rather, the process seems more like being on an ocean liner that is turning around. The process is so gentle that you are not aware that it is even happening, but at some point you realize that you are facing in a different direction. There may be a moment of realization that you now believe something that you did not before, but that moment is just an explicit acknowledgment of something that that you had already tacitly accepted.

What started the process of change could be one of many factors – something you read, a news item, a discussion with a friend, some major public event – whose implications you may not be immediately aware of. But over time these little things lodge in your mind, and as your mind tries to integrate them into a coherent framework, your views start to shift. For me personally, I enjoy discussions of deep ideas with people I like and respect. Even if they do not have any expertise in this area, discussions with such people tend to clarify one’s ideas.

I can see that process happening to me right now with the ideas about the brain. I used to think that the brain was quite plastic, that any of us could be anything given the right environment. I am not so sure now. The work of Chomsky on linguistics, the research on how people learn, and other bits and pieces of knowledge I have read have persuaded me that it is not at all clear that the perfectly-plastic-brain idea can be sustained. It seems reasonable that some structures of the brain, especially the basic ones that enable it to interpret the input from the five senses, and perhaps even learn language, must be pre-existing.

But I am not completely convinced of the socio-biological views of people like E. O. Wilson and Steven Pinker who seem to argue that much of our brains, attitudes, and values are biologically determined by evolutionary adaptation. I am also not convinced of the value of much of popular gender-related differences, such as that men are better than women at math or that women are more nurturing than men. That seems to me to be a little too pat. I am always a little skeptical of attempts to show that the status quo is ‘natural’ since that has historically been used to justify inequality and oppression.

But the works of cognitive scientists are interesting and I can see my views on how the brain works changing slowly. One sign of this is my desire to read widely on the subject.

So I am currently in limbo as regards the nature of the brain, mulling things over. At some point I might arrive at some kind of unified and coherent belief structure. And after I do so, I may well wonder if I ever believed anything else. Such are the tricks the brain can play on you, to make you think that what you currently believe is what is correct and what you always believed.

POST SCRIPT: The Church of the Wholly Undecided

Les Barker has a funny poem about agnosticism.

The purpose of teaching

(I am taking a short vacation from new blog posts. I will begin posting new entries again, on August 27, 2007. Until then, I will repost some early ones. Today’s one is from March 24, 2005, edited and updated.)

I have been teaching for many years and encountered many wonderful students. I remember in particular two students who were in my modern physics courses that dealt with quantum mechanics, relativity, and cosmology.

Doug was an excellent student, demonstrating a wonderful understanding of all the topics we discussed in class. But across the top of his almost perfect final examination paper, I was amused to see that he had written, “I still don’t believe in relativity!”

The other student was Jamal and he is not as direct as Doug. He came into my office a few years after the course was over (and just before he was about to graduate) to say goodbye. We chatted awhile, I wished him well, and then as he was about to leave he turned to me and said hesitantly in his characteristically shy way: “Do you remember that stuff you taught us about how the universe originated in the Big Bang about 15 billion years ago? Well, I don’t really believe all that.” After a pause he went on, “It kind of conflicts with my religious beliefs.” He looked apprehensively at me, perhaps to see if I might be offended or angry or think less of him. But I simply smiled and let it pass. It did not bother me at all.

Why was I not upset that these two students had, after having two semester-long courses with me, still not accepted the fundamental ideas that I had been teaching? The answer is simple. The goal of my teaching is not to change what my students believe. It is to have them understand what practitioners in the field believe. And those are two very different teaching goals.

As I said, I have taught for many years. And it seems to me that teachers encounter three kinds of situations with students.

One is where students do not have much prior experience (either explicitly or implicitly) with the material being taught and don’t have strong feelings about it either way. This is usually the case with technical or highly specialized areas (such as learning the symptoms of some rare disease or applying the laws of quantum mechanics to the hydrogen atom). In such cases, students have little trouble accepting what is taught.

The second type of situation is where students’ life experiences have resulted in strongly held beliefs about a particular knowledge structure, even though the student may not always be consciously aware of having such beliefs. The physics education literature is full of examples that our life experiences conspire to create in people an Aristotelian understanding of mechanics. This makes it hard for them to accept Newtonian mechanics. Note that this difficulty exists even though the students have no particular attachment to Aristotle’s views on mechanics and may not have the faintest idea what they are. Overcoming this kind of implicit belief structure is not easy. Doug was an example of someone who had got over the first hurdle from Aristotelian to Newtonian mechanics, but was finding the next transition to Einsteinian relativistic ideas much harder to swallow.

The third kind of situation is where the student has strong and explicit beliefs about something. These kinds of beliefs, as in the case of Jamal, come from religion or politics or parents or other major influences in their lives. You cannot force such students to change their views and any instructor who tries to do so is foolish. If students think that you are trying to force them to a particular point of view, they are very good at telling you what they think you want to hear, while retaining their beliefs. In fact, trying to force or bully students to accept your point of view, apart from being highly unethical teaching practice, is a sure way of reinforcing the strength of their original views.

So Doug’s and Jamal’s rejection of my ideas did not bother me and I was actually pleased that they felt comfortable telling me so. They had every right to believe whatever they wanted to believe. But what I had a right to expect was that they had understood what I was trying to teach and could use those ideas to make arguments within those frameworks.

For example, if I had given an exam problem that required that the student demonstrate his understanding of relativistic physics to solve, and Doug had refused to answer the question because he did not believe in relativity or had answered it using his own private theories of physics, I would have had to mark him down.

Similarly, if I had asked Jamal to calculate the age of the universe using the cosmological theories we had discussed in class, and he had instead said that the universe was 6,000 years old because that is what the Bible said, then I would have to mark him down too. He is free to believe what he wants, but the point of the course is to learn how the physics community interprets the world, and be able to use that information.

Understanding this distinction is important because of the periodic appearance of demagogues who try to frighten people by asserting that colleges are indoctrinating students to think in a particular way. Such people seem to assume that students are like sheep who can be induced to believe almost anything the instructor wants them to and thus require legal protection. Anyone who has taught for any length of time and has listened closely to students will know that this is ridiculous. It is not that students are not influenced by teaching and do not change their minds but that the process is far more complex and subtle than it is usually portrayed, as I will discuss in the next posting.

My own advice to students is to listen carefully and courteously to what knowledgeable people have to say, learn what the community of scholars thinks about an issue, and be able to understand and use that information when necessary. Weigh the arguments for and against any issue but ultimately stand up for what you believe and even more importantly know why you believe it. Don’t ever feel forced to accept something just because some ‘expert’ or other authority figure (teacher, preacher, parent, political leader, pundit, or media talking head) tells you it is true. Believe things only when it makes sense to you and you are good and ready for it.

“I know this is politically incorrect but . . .”

(I am taking a short vacation from new blog posts. I will begin posting new entries again, on August 27, 2007. Until then, I will repost some early ones. Today’s one is from August 14, 2006, edited and updated.)

One of the advantages of being older is that sometimes you can personally witness how language evolves and changes, and how words and phrases undergo changes and sometimes outright reversals of meaning.

One of the interesting evolutions is that of the phrase “politically correct.” It was originally used as a kind of scornful in-joke within Marxist political groups to sneer at those members who seemed to have an excessive concern with political orthodoxy and who seemed to be more preoccupied with vocabulary than with the substance of arguments and actions.

Later it became used as a weapon against those who were trying to make language more nuanced and inclusive and less hurtful, judgmental, or discriminatory. Such people advocated using “disabled” instead of “crippled” or “mentally ill” instead of “crazy,” or “hearing impaired” instead of “deaf” and so on in an effort to remove the stigma under which those groups had traditionally suffered. Those who felt such efforts had been carried to an extreme, or just wanted to use words the way they always had, disparaged those efforts as trying to be “politically correct.”

The most recent development has been to shift the emphasis from sneering at the careful choosing of words to sneering at the ideas and sentiments behind those words. The phrase has started being used pre-emptively, to shield people from the negative repercussions of stating views that otherwise may be offensive or antiquated. This usage usually begins by saying “I know this is politically incorrect but….” and then finishes up by making a statement that would normally provoke quick opposition.

So you can now find people saying “I know this is politically incorrect but perhaps women are inferior to men at mathematics and science” or “I know this is politically incorrect but perhaps poor people are poor because they are stupid” or “I know this is politically incorrect but perhaps blacks are less capable than whites at academics.” The opening preamble is not only designed to make such statements acceptable, the speaker can even claim the mantle of being daring and brave, an outspoken and even heroic bearer of unpopular or unpalatable truths.

Take for example, a blurb by intelligent design creationist Jonathan Wells for his own book The Politically Incorrect Guide to Darwinism and Intelligent Design. The cover of the book says: “Darwin is an emperor who has no clothes— but it takes a brave man to say so. Jonathan Wells, a microbiologist with two Ph.D.s (from Berkeley and Yale), is that brave man.” There have been similar books that try this same linguistic maneuver, such as The Politically Incorrect Guide to Science and The Politically Incorrect Guide to Global Warming (and Environmentalism).

Brandishing the label of being ‘politically incorrect’ as a form of argument is silly, as is invoking the fact that one has a doctorate. It is actually a sign of weakness, indicating that one’s arguments cannot stand on their own. For example, physicists assume that all electrons are identical. We don’t really know this for a fact, since it is impossible to compare all electrons. The statement “all electrons are identical” is a kind of default position and, in the absence of evidence to the contrary, does not need to be supported by positive evidence. The assertion that “some electrons are heavier than others” is going to be dismissed in the absence of supporting evidence. Simply saying ” I know this is not politically correct but I believe some electrons are heavier than others and I have a PhD” does not make it any more credible. It merely makes you look pompous and self-aggrandizing.

Sentiments that would normally would be considered discriminatory, biased, and outright offensive if uttered without any supporting evidence are now protected from criticism by this preamble. It is then the person who challenges this view who is put on the defensive, as if he or she was some prig who unthinkingly spouts an orthodox view.

Fintan O’Toole of The Irish Times (May 5, 1994) noted this trend early and pithily said:

We have now reached the point where every goon with a grievance, every bitter bigot, merely has to place the prefix, “I know this is not politically correct but . . .” in front of the usual string of insults in order to be not just safe from criticism but actually a card, a lad, even a hero. Conversely, to talk about poverty and inequality, to draw attention to the reality that discrimination and injustice are still facts of life, is to commit the new sin of political correctness……… Anti-PC has become the latest cover for creeps. It is a godsend for every sort of curmudgeon or crank, from the fascistic to the merely smug.

Hate blacks? Attack positive discrimination – everyone will know the codes. Want to keep Europe white? Attack multiculturalism. Fed up with the girlies making noise? Tired of listening to whining about unemployment when your personal economy is booming? Haul out political correctness and you don’t even have to say what’s on your mind.

Even marketers are cashing in on this anti-PC fad, as illustrated by this cartoon.

Here’s a tip. Anyone who feels the need to invoke the “politically incorrect” trope as an indicator of his or her valor is probably trying to hide the weaknesses in their argument.

POST SCRIPT: Comparing the candidates

How do the presidential candidates compare when it comes to where they stand on the left-right and authoritarian-libertarian continua?

You can see for yourself, based on their positions on a range of issues.

I found it interesting (but not surprising) that every candidate of both parties (except for Democrats Dennis Kucinich and Mike gravel) ended up in the right-wing /authoritarian quadrant.

You can also answer the questions yourself and compare yourself to them. My scores put me in the deep southwest part in the left-libertarian quadrant, more so than Kucinich and Gravel.

These kinds of things are fun but should not be considered a serious analysis of political philosophies.

What do creationist/ID advocates want-III?

(I am taking a short vacation from new blog posts. I will begin posting new entries again, on August 27, 2007. Until then, I will repost some very early ones, updated if necessary. Today’s one is from March 18, 2005, edited and updated.)

It is time to tackle head-on the notion of what is meant by the ‘materialism’ that the intelligent design creationism (IDC) camp find so distasteful. (See part I and part II for the background.)

The word materialism is used synonymously with ‘naturalism’ and perhaps the clearest formulation of what it means can be found in the writings of paleontologist George Gaylord Simpson who said in Tempo and Mode in Evolution (p. 76.):

The progress of knowledge rigidly requires that no non-physical postulate ever be admitted in connection with the study of physical phenomena. We do not know what is and what is not explicable in physical terms, and the researcher who is seeking explanations must seek physical explanations only. (Emphasis added)

Simpson was by not an atheist (as far as I can tell) but he is saying something that all scientists take for granted, that when you seek a scientific explanation for something, you look for something that has natural causes, and you do not countenance the miraculous or the inscrutable. This process is more properly called ‘methodological naturalism’, to be contrasted with ‘philosophical naturalism.’

Despite the polysyllabic terminology, the ideas are easy to understand. For example, if you hear a strange noise in the next room, you might wonder if it is a radiator or the wind or a mouse or an intruder. You can systematically investigate each possible cause, looking for evidence. For each question that you pose, the answer is sought in natural causes. You would be unlikely to say: “The noise in the next room is caused by god throwing stuff around.” In general, people don’t invoke god to explain the everyday phenomena of our lives, even though they might be quite religious.

Methodological naturalism is just that same idea. Scientists look for natural explanations to the phenomena they encounter because that is the way science works. Such an approach allows you to systematically investigate open questions and not shut off avenues of research. Any scientist who said that an experimental result was due to God intervening in the lab would be looked at askance, not because other scientists are all atheists determined to stamp out any form of religion but because that scientist would be violating one of the fundamental rules of operation. There is no question in science that is closed to further investigation of deeper natural causes.

Non-scientists sometimes do not understand how hard and frustrating much of scientific research is. People work for years and even decades banging their heads against brick walls, trying to solve some tough problem. What keeps them going? What makes them persevere? It is the practice of methodological naturalism, the belief that a discoverable explanation must exist and that it is only their ingenuity and skill that is preventing them from finding the solution. Unsolved problems are seen as challenges to the skills of the individual scientist and the scientific community, not as manifestations of god’s workings.

This is what, for example, causes medical researchers to work for years to find causes (and thus possibly cures) for rare and obscure diseases. Part of the reason is the desire to be helpful, part of it is due to personal ambition and career advancement, but an important part is also the belief that a solution exists that lies within their grasp.

It is because of this willingness to persevere in the face of enormous difficulty that science has been able to make the breakthroughs it has. If, at the early signs of difficulty in solving a problem scientists threw up their hands and said “Well, looks like god is behind this one. Let’s give up and move on to something else” then the great discoveries of science that we associate with Newton, Darwin, Einstein, Planck, Heisenberg, etc. would never have occurred.

For example, the motion of the perigee of the moon was a well-known unsolved problem for over sixty years after the introduction of Newtonian physics. It constituted a serious problem that resisted solution for a longer time than the problems in evolution pointed to by IDC advocates. Yet no supernatural explanation was invoked, eventually the problem was solved, and the result was seen as a triumph for Newtonian theory.

So when IDC advocates advocate the abandonment of methodological naturalism, they are not trying to ease just Darwin out of the picture. They are throwing out the operational basis of the entire scientific enterprise.

Philosophical (or ontological) naturalism, as contrasted with methodological naturalism, is the belief that the natural world is all there is, that there is nothing more. Some scientists undoubtedly choose to be philosophical naturalists (and thus atheists) because they see no need to have god in their philosophical framework, but as I said in an earlier posting, others reject that option and stay religious. But this is purely a personal choice made by individual scientists and it has no impact on how they do science, which only involves using methodological naturalism. There is no requirement in science that one must be a philosophical naturalist, and as I alluded to earlier, there is little evidence that Gaylord Simpson was a philosophical naturalist although he definitely was a methodological naturalist.

The question of philosophical naturalism is, frankly, irrelevant to working scientists. Scientists don’t really care if their colleagues are religious or not. I have been around scientists all my life. But apart from my close friends, I have no idea what their religious beliefs are, and even then I have only a vague idea of what they actually believe. I know that some are religious and others are not. Whether a scientist is a philosophical naturalist or not does not affect how his or her work is received by the community. It just does not matter.

But what the IDC advocates want, according to their stated goal of “If things are to improve, materialism needs to be defeated and God has to be accepted as the creator of nature and human beings” is to enforce the requirement that scientists reject both philosophical and methodological naturalism. They are essentially forcing two things on everyone:

  • Requiring people to adopt the IDC religious worldview as their own.
  • Requiring scientists to reject methodological naturalism as a rule of operation for science.

In other words, IDC advocates are not asking us to reject only Darwin or to turn the scientific clock back to the time just prior to Darwin, they want us to go all the way back to before Copernicus, and reject the very methods of science that has enabled it to be so successful. They want us to go back to a time of rampant and unchecked superstition.

This is not a good idea.

What do creationist/ID advocates want-II?

(I am taking a short vacation from new blog posts. Until I begin posting again, which should not be more than a couple of weeks, I will repost some very early ones, updated if necessary. Today’s one is from March 16, 2005, edited and updated.)

We saw in an earlier posting that a key idea of the creationists is that it was the arrival of the ideas of Darwin, Marx, and Freud that led to the undermining of Western civilization.

The basis for this extraordinary charge is the claim that it was these three that ushered in the age of materialism. These three people make convenient targets because, although they were all serious scientific and social scholars, they have all been successfully tarred as purveyors of ideas that have been portrayed as unpleasant or even evil (Darwin for saying that we share a common ancestor with apes, Marx with communism, Freud with sexuality).
[Read more…]

What do creationist/ID advocates want-I?

(I am taking a short vacation from new blog posts. Until I begin posting again, which should not be more than a couple of weeks, I will repost some very early ones, updated if necessary. Today’s one is from February 24, 2005, edited and updated.)

In an earlier posting, I spoke about how those who view Darwin’s ideas as evil see it as the source of the alleged decline in morality. But on the surface, so-called ‘intelligent design creationism’ (or IDC) seems to accept much of evolutionary ideas, reserving the actions of a ‘designer’ for just a very few (five, actually) instances of alleged ‘irreducible complexity’ that occur at the microbiological level.

This hardly seems like a major attack on Darwin since, on the surface, it seems to leave unchallenged almost all of the major ideas of the Darwinian structure such as the non-constancy of species (the basic theory of evolution), the descent of all organisms from common ancestors (branching evolution), the gradualness of evolution (no discontinuities), the multiplication of species, and natural selection.
[Read more…]

Evolution and moral decay

(I am taking a short vacation from new blog posts. Until I begin posting again, which should not be more than a couple of weeks, I will repost some very early ones, updated if necessary. Today’s one is from February 24, 2005, edited and updated.)

In a previous posting, I discussed why some religious people found evolutionary theory so distressing. It was because natural selection implies that human beings were not destined or chosen to be what they are.

While I can understand why this is upsetting to religious fundamentalists who believe they were created specially in God’s image and are thus part of a grand cosmic plan, there is still a remaining puzzle and that is why they are so militant about trying to have evolution not taught in schools or undermining its credibility by inserting fake cautions about it. After all, if a person dislikes evolutionary theory for whatever reason, all they have to do is not believe it.
[Read more…]

Can we ever be certain about scientific theories?

(I am taking some time off from new blog posts. Until I begin posting again, which should not be more than a couple of weeks, I will repost some very early ones, updated if necessary. Today’s one is from February 17, 2005.)

A commenter to a previous posting raised an interesting perspective that requires a fresh posting, because it reflects a commonly held view about how the validity of scientific theories get established.

The commenter says:

A scientist cannot be certain about a theory until that theory has truly been tested, and thus far, I am unaware of our having observed the evolution of one species from another species. Perhaps, in time, we will observe this, at which point the theory will have been verified. But until then, Evolution is merely a theory and a model.

While we may have the opportunity to test Evolution as time passes, it is very highly doubtful that we will ever be able to test any of the various theories for the origins of the Universe.

I would like to address just two points: What does it mean to “test” a theory? And can scientists ever “verify” a theory and “be certain” about it?
[Read more…]

Evolution-21: Why evolution speeds up with time

(Please see here for previous posts in this series.)

One of interesting things about evolution is that it seems to be speeding up with time. Earth was formed about 4.7 billion years ago and it took about a billion years for the first single-celled life to appear about 3.5 billion years ago. It then took another 2.5 billion years for the first multi-cellular life form (like sponges) to appear. So everything else, all the insects, animals, and birds, came into being within the last one billion years or so.
[Read more…]

Petitions and politics in science

In a recent discussion on a listserv for physics teachers, someone strongly recommended the book The Politically Incorrect Guide to Science by Tom Bethell, saying that it exposed how mainstream science was suppressing some ideas for non-science reasons, in particular how the great weaknesses of evolutionary theory were being hidden.

I had not read this book myself but these kinds of arguments are familiar to me and Bethell had written an article describing his own book. It struck me as extraordinarily shallow, rehashing arguments that have long been discredited, and invoking misleading (and old) chestnuts about evolution occurring only by chance, and missing transitional forms, etc. In fact, he seemed to have drawn his arguments against evolution from the playbook of the intelligent design creationists, in particular Jonathan Wells’ book Icons of Evolution.

He even made the argument that the only thing that has been seen is ‘microevolution’ (small changes within species) and not macroevolution (change from one species to another). But the distinction drawn between micro- and macroevolution is untenable, since it has long been realized that there is a large overlap between varieties within species and between species as a whole, making the drawing of such distinctions difficult. Darwin himself pointed this out in his On the Origin of Species (chapter II), where he emphasized how difficult it was for even experts to classify whether animals were varieties within a single species or different species.

It is amazing that in this day and age people like Bethell still bring up Haeckel’s embryos. Modern biologists don’t take Haeckel’s misleading sketches seriously anymore since his theory was discredited more than a hundred years ago and only intelligent design creationists (IDC) keep bringing it up repeatedly to argue that scientists falsify things in order to buttress the case for evolution. In the documentary A Flock of Dodos IDC advocate John Calvert talks about how biology textbooks use Haeckel’s figures to mislead children but when asked to show this, thumbs through some textbooks and cannot find any examples. He had simply accepted this folklore uncritically. What use Haeckel has now is purely pedagogical.

The Haeckel case is analogous to someone finding that the Bohr model of the atom is still being taught in middle school science textbooks, “discovering” that Bohr’s model violates Maxwell’s laws of electromagnetism, and thus concluding that quantum mechanics is wrong and that children are being misled into accepting it. Quantum mechanics has come a long way since the Bohr atom and does not depend on it, just like evolutionary biology and Haeckel’s embryos. To keep bringing it up is a sign of desperation

Bethell’s argument about the fact that no one has seen half-bats and that therefore step-by-step evolution could not have occurred, reminds me of those people who say that it is absurd that an electron can go through two slits or that twins age differently based on their speeds. After all, has anyone actually SEEN an electron go through two slits? Has anyone actually SEEN twins age differently? If we haven’t seen such things directly, they must not occur, right? I have described earlier how incomplete the fossil record is, because fossilization is extremely unlikely, and how arguments that depend on the existence of gaps in the fossil record can never be satisfied because new gaps can always be created.

As I have said in this series on evolution, to really appreciate the theory one has to get beyond the simple minded rhetoric of the kind that Bethell indulges in and look at the underlying details and the mathematics. The question of whether evolution is a “fact” is a red herring. “Theory” and “fact” are fluid terms in science. What is true is that the fully developed theory of evolution, known as the neo-Darwinian synthesis, is the most productive and useful theory in biology today, and forms the basis of almost all research in that field.

People who dislike the theory of evolution often point to the petition that the Discovery Institute (DI), the main driver of Intelligent Design Creationism (IDC), put out signed by 700 people that says: “We are skeptical of claims for the ability of random mutation and natural selection to account for the complexity of life. Careful examination of the evidence for Darwinian theory should be encouraged.” Such people cite this as evidence that the theory is weak and then ask: “Why are so many scientists jumping off the evolution band wagon?”

But scientists are taught to be skeptical and to examine carefully the evidence for any theory. And if a theory (like evolution) challenges their religious beliefs, they are likely to be even more skeptical of it. That is a natural human tendency. It does not take any effort for a mathematician or physicist or philosopher to say she is skeptical of evolution, just as it does not cost any biologist anything to say that he is skeptical of the big-bang. After all, in each case, they are not personally working with that theory and are unlikely to know anything about it in any detail and thus can let other factors have a greater influence. As of the time when there were 400 people who had signed on, about 80% were not even biologists. (The story of one religious scientist who signed on to the Discovery Institute statement and only later realized what was going on can be read here.)

Another problem with the petition wording is that although Darwin proposed the mutation and natural selection mechanism, developments since then have added other mechanisms such as gene flow and genetic drift, so even a biologist who sees no problem with evolution would agree that mutation and natural selection alone are not sufficient.

I personally am skeptical of ANY theory in ANY field as being the last word (or the ‘truth’) on the subject because the history of science teaches us that scientific theories have always been provisional. So for me the DI statement itself is nothing more than a platitude. The fundamental issue is whether the biological community feels that evolution is in a crisis, and as far as I am aware, the biological science community does not think so and continues to use that theory as the foundation for their work. So these kinds of statements are just meaningless. When biologists start using alternative theories to generate predictions and start getting positive results, then we can take those other theories seriously.

It is important to realize that despite so many years of pushing intelligent design creationism, the people at the Discovery Institute have not been able to generate even one prediction, let alone do any experiments to investigate their theory. What they are doing is not science, it is lobbying and public relations.

Statements like the ones put out by the Discovery Institute on evolution are, however, useful as indicators of what people desire or yearn for.

For example, I am skeptical of the idea of dark matter as the explanation for the anomalous velocity distribution of stars on the arms of spiral galaxies. Why? Mostly for aesthetic reasons. It seems a bit contrived to me and the idea of huge amounts of matter surrounding us that we cannot detect reminds me uncomfortably of the arguments for the ether before Einstein’s theory showed that the ether was a redundant concept.

I am hoping that a nicer theory than dark matter comes along and I know I am not alone in feeling this way and that other card-carrying physicists share my view. So if someone handed me a petition saying that I was skeptical of the theory of dark matter and would like the evidence for it to be examined carefully, that statement’s content would not be objectionable to me. I would totally agree.

But I would not sign because it is pointless. I have not done any real work to support my misgivings. I have not developed an alternative theory, generated hypotheses, made predictions, or explained any existing data. Physicists who actually work on the spiral galaxy problem (even if they were completely outnumbered by the people who sign a petition dismissing dark matter theory) would be perfectly justified in ignoring me and any other physicists who sign such a petition in the absence of any substantive counter-theory.

What the DI petition on evolution tells us is that there are about 700 people who wish and hope that a theory more congenial to them than evolution comes along. That’s fair enough but hardly major news. They have every right to feel that way and to say so. But it is by no means a measure of the merits of the theory, however many people sign on to it, and it is dishonest of the Discovery Institute to make such a claim.

Bethell’s thesis that the scientific community is conspiring to suppress the truth about the weaknesses of evolution is silly. Given that the US has high levels of religiosity and public skepticism about evolution and widespread unease that evolution is undermining religious beliefs, any scientist who found good evidence for special creation would be deluged with funding from both government and private sources and receive high visibility and acclaim. Furthermore, such a discovery would open up vast new areas of research. In such a climate, why would any scientist not publish findings that provided evidence for special creation?

People like Bethell are trying to achieve by public relations what they cannot do using science. They are not the first to try to do this and will not be the last. But they will fail, just like their predecessors.

POST SCRIPT: The insanity of the employer-based health care system

This question posed at a Democratic presidential candidates forum illustrates perfectly why we need a single-payer, universal health care system.