Saturday, March 13, 2010

On disagreement in science

As part of my essay on how science works, I described the notion that science operates on two important principles.

1. At any given time, those who engage in scientific research on a particular topic will have developed a consensus that represents a core of agreement regarding that topic among the majority of researchers. This consensus isn't some immutable truth - it's simply the view of the majority at that time. Nor is this consensus typically voted upon and approved by some sanctioning body.

2. At any given time, there may be one or more (perhaps many more) of those engaged in that research who disagree with the consensus. They're seeking to modify that consensus, changing it to one consistent with their dissenting understanding. Such disagreements are a natural part of the scientific process, not some sort of unfortunate conflict that signals a problem for the science.

Scientific consensus is the basis for how science proceeds in a systematic search for understanding. We proceed from the consensus, we teach the consensus, and the consensus is our guide for how to proceed. Overthrowing that consensus (so-called "paradigm shifts") is properly seen as the result of requiring the advocate(s) of some proposed new vision to provide extraordinarily convincing evidence. This process is logically and necessarily a "conservative" one. If our scientific understanding can be swept aside on flimsy evidence at the whim of an individual or subgroup, then it wouldn't represent anything substantial at all. This conservative character of scientific consensus sometimes makes those who wish to change that consensus angry and they may resort to all sorts of tricks to get their opinions heard, including airing their views in the media rather than engaging in the discourse associated with refereed scientific journals. Scientists are human and many of us have large egos - some without much basis for that large ego, of course.

Consider three scientific topics out of many: Global Climate Change, Tornadogenesis, and Evolutionary Biology. In each topic, I'll discuss different aspects of the debate about the consensus.

1. Global Climate Change. The overwhelming majority of those engaging in global climate change research is represented by the reports of the Intergovernmental Panel on Climate Change (IPCC). This is a rare example of a consensus arrived at with a vote of the participants. No doubt that step is needed to make it clear to non-scientists that this is indeed a consensus.

The "deniers" within the group of those actually engaged in climate change research (a larger group than the IPCC representatives) represent a very small minority, and most of them accept most of the IPCC's conclusions, only arguing for what amount to minor changes. Most of the "deniers" come from outside of the climate change research community, and many are quite far from being scientists at all (e.g., "pundits" such as Rush Limbaugh, Bill O'Reilly, Glenn Beck, etc.). Some are scientists in other fields. My point here is not to go into all of this debate once again, but to indicate that most of the public debate is between those not actually engaged in climate change research with those who are so engaged in and publishing papers in that particular field. If one were going to characterize the intra-science debate on this topic, it would necessarily be very one-sided, with the overwhelming majority supporting the IPCC. A "fair and balanced" argument between a real global climate change research and some skeptic from outside the field is a meaningless argument. It's not "fair and balanced", like some journalistic notion of "equal time" for the two viewpoints. The two viewpoints are inherently unequal. One represents the science of global climate change and the other represents ... whatever.

The reason for all of the uproar is that if global climate change has a large anthropogenic component and if the climate change processes we believe are underway continue to accelerate as a result of what we humans are doing, then any remedial actions could have negative consequences for certain elements of our society who have a strong pecuniary interest in the status quo. It's to their financial and/or political advantage to portray the science of global climate change as either some vast conspiracy against our society or as a scientific topic that needs to be "settled" once and for all before we actually do anything - that might threaten their particular special interests. [As discussed in my essay, scientific issues generally are not settled once and for all, ever! To expect so is a major misunderstanding of the scientific process.]

2. Tornadogenesis. There exist several different "factions" within the community of scientists regarding the topic of tornadogenesis. There is, of course, a considerable foundation of consensus in which they all operate, but folks don't necessarily agree about the details of the processes by which tornadoes are formed. If we were to write a textbook that would include a discussion of tornadoes, would it be appropriate to include the arguments currently ongoing about tornadogenesis? For the most part, the issues that divide tornado researchers are esoteric and operating at a level that would require an understanding of the consensus to even begin to grasp those arguments. Hence, a textbook for those learning about tornadoes shouldn't necessarily include a "fair and balanced" presentation of all those various viewpoints! Rather, it should summarize the scientific consensus - the bedrock of the science at any given moment. The fact that that consensus changes from time to time is reflected in the need for new textbooks from time to time. No big deal here.

Note that tornadogenesis researchers are not engaging in a bitter, protracted public debate within the media - they're not appearing on talk shows and engaging in videotaped verbal clashes with outsiders who have some contrary opinion regarding how tornadoes form. Crackpots email me from time to time to share their wild ideas on tornadogenesis. Would a debate between me and such a crackpot represent a meaningful and informative piece of journalism on the evening news? Such a debate would be silly and meaningless in the extreme, of course.

Furthermore, the "Horatio Alger" story of outsiders coming into a branch of science (perhaps from some other science, or perhaps not) and contributing revolutionary and important new ideas is mostly a myth. It happens, but only very rarely. When it does happen, the evidence must meet the criterion of being extraordinarily convincing - as was the case for the notion of continental drift proposed by the meteorologist Alfred Wegener. His story is significant in part because such an enormous paradigm shift from an "outsider" is so rare! And the convincing evidence came well after his death.

As of this time, there are no large economic issues tied to our scientific understanding of tornadoes. No political or religious group is objecting to the use of the vorticity equation (and other tools of research) as a means of illuminating tornadogenesis. There's no "creationist" or "political" version of tornadogenesis demanding "equal time" in the scientific journals, TV, and textbooks. To have a version of "God created tornadoes" advanced as a scientific hypothesis comparable to current tornadogenesis ideas is so laughable as to not deserve a nanosecond's worth of attention. In fact, of course, no one is advancing such a silly idea ... yet. I offer this absence of public debate regarding tornadogenesis as something for the global climate change deniers and creationists to ponder.

3. Evolutionary biology. In this "debate" being waged in various places throughout our society (legislative bodies, school boards, town meetings, etc.), the science of evolutionary biology is being assailed almost totally by non-scientists, seeking to inject their religious views in our schools and elsewhere. The representation of the "creationist" viewpoint as science is completely without foundation, as I've explained elsewhere (and many others have done so, of course). The notion of this being a "fair and balanced" representation of science is so utterly without substance that it would laughable, were it not being taken seriously by religious right-wing politicians, school board members, and textbook publishers. The points of debate here are not the equivalent of those between adherents of the scientific consensus and those minority scientists seeking to modify that consensus. This debate is almost completely between science and non-science. Scientific consensus is virtually unanimously in support of evolutionary biology. Any opinion outside of that consensus has yet to offer any meaningful evidence to gainsay evolution. To represent the two viewpoints in a textbook as equal elements of a scientific debate is absolutely without any basis. A potential outcome from representing this as a scientific argument is to expand on the already expanding ignorance of science resulting from the failures of our K-12 education process.

Science is arguably the most preeminently rational kind of thought. Logic is an essential element of the process and there's no place for politics and religion in science. To see it being misrepresented is both infuriating and depressing. We as a nation seem to be descending away from enlightenment toward the demon-haunted world of mythology and irrationality. Our nation's "Founding Fathers" were overwhelmingly a product of the Enlightenment, who had hopes that the United States of America could become a haven for rational thought and democratic principles, free from an imposed state religion, where dissent would be cherished for its ability to keep the tyranny of the majority in check. We seem steadily to be moving away from that vision. The choice remains ours, for the time being, but if we continue down this path of irrationality and "our side is always right", who knows what choices we will come to have? See the theocratic governments of the Islamist Middle East for a preview of what may be in store for us.

Three Cultures? Or one?

Of late, I’ve been slowly working through a book: "The Three Cultures" by Jerome Kagan. This is a work that pays homage in its title to C.P. Snow’s classic work, "The Two Cultures", in which Snow described and attempted a reconciliation between the seemingly very different cultures of science and the humanities. In Kagan's book, the author (a social scientist) adds a third culture by distinguishing between “natural” sciences and social sciences, the latter of which focus on human beings and their activities in various ways (political science, economics, sociology, psychology, etc.). Kagan divides the "science" culture into two ...

I’m not going to delve into this book’s notions - maybe later. But reading it has forced me to mull over the divisions among the diverse human “cultures”. Of particular significance is that being a physical scientist has given me a broad perspective - in a position to grasp challenging scientific concepts based on a knowledge of advanced mathematics. Those in this position are relatively rare. I don’t know the numbers, but I’m guessing that simply knowing Calculus puts me into a very tiny minority (of order 1% or less) of humans in my country, to say nothing of those in other nations (“worlds” apart, in nations where most people have little chance to pursue a career in science, regardless of their talent and interest).

And I'm also human, with all the same feelings and perspectives that those pursuing careers in the humanities have. Science inevitably colors those aspects of my perspective, naturally - nevertheless, I see the beauty of a rose as well as the next human. I also see deeper than that, to the processes allowing that rose to happen in my world. It's my privilege to live at a time and place where science has added considerable understanding about the world for all of us who choose to gain that understanding.

I know many scientists who dabble in other fields of endeavor, including many who are artists of various sorts – visual arts, performing arts, etc. Some of them are reasonably well-accomplished in their hobbies. Not full-time professionals certainly, but serious enough about those hobbies to develop considerably their talents in those directions. Most good scientists are far from one-dimensional geeks, despite the widespread myth that all scientists are one-dimensional.

Unfortunately, I know very few folks who are the inverse of my colleagues - that is, professionals in the humanities but simultaneously pursuing some scientific interest at a serious level. [Many of the exceptions to this rule amongst those I know are storm chasers!] This means that scientists well may be more than able to grasp non-science concepts, but few of those pursuing careers outside of science have much of a clue about how science really works. Their bias against science comes, perhaps, from hated science courses in K-12 education, which they rejected as of no interest and boring in the extreme. Math phobia also takes a toll of the potentially interested. Unfortunately ignorance of how science works perpetuates myths about, say, the conflict between evolutionary biology and creationism. Myths fill the vacuum created by rejected understanding.

It’s my hope that this essay won’t come across as encouraging or perpetuating a divide between science and the humanities. My experience suggests that the concept advanced by C.P. Snow is true - that the two cultures have some elements in common and could viably interact, to the benefit of everyone. But it’s been my perception that most non-scientists have erected a barrier in their own minds to the value and excitement of learning about the natural world in a scientific way. To them, knowing a rose’s biology somehow detracts from our appreciation of the rose as an object of beauty or a symbol of something relating to the human condition. I couldn’t disagree more with that thesis, but it’s impossible to change the mind of someone who has chosen to remain ignorant of the inherently beautiful perspective associated with knowing how things work.

I can’t imagine how the modern Western world of today, with its deep roots in science and technology, must appear to someone who has trouble understanding the information content of a graph. As I suggested earlier, that ignorance breeds the growth of faith-based mythology. In today's world, where important social decisions ride on scientific issues, the growth of that mythology as a means of making societal decisions is inherently dangerous.

Whatever their world view, folks ignorant of science and how it works are separated by a vast gulf from the world as I know it. That saddens me, because I enjoy discourse with people who are informed enough to have a substantive understanding of some topic. Finding myself "preaching to the choir" is a less than satisfactory experience - I'm not seeking affirmation of my ideas by murmured agreement in a crowd of the faithful. Rather, I welcome challenges to my understanding, provided they're intelligent challenges, and not simple bashing. By the same token, a clash of ideas that results in no one changing their minds still can be useful and stimulating, provided the discourse remains civil (see my earlier blog about civil discourse).

C.P. Snow bemoaned the division of our society into two apparently different "cultures". Today, the fractionation of our society is rolling forward at an accelerating pace. We're mostly talking past each other, not engaging in a search for understanding and reconciliation where possible. Dehumanizing those with opposing views is rampant on all sides. If we're to survive the storm we're creating for ourselves, I think we need to welcome dissent in the way that our nation's "Founding Fathers" hoped would happen - in the way expressed so eloquently on a plaque affixed to Bascom Hall at the University of Wisconsin.