So what? If I said that 97-98% of cancer researchers believed that smoking caused cancer, or if 97-98% of astronomers believed that the Earth revolved around the Sun, you would all be laughing at how trivially obvious it is. But when we discuss climate change, consensus plays a big (and controversial) role in the debate.
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| Response to the survey question "Do you think human activity is a significant contributing factor in changing mean global temperatures?" (Doran 2009) General public data come from a 2008 Gallup poll. Image from SkepticalScience.com |
It should be first noticed that it is an invalid argument to claim that "because 97-98% of experts something is true, it must be true". This argumentum ad numerum implies the truth of a proposition from only the popularity of its belief. It is not difficult for anyone to think of counterexamples which show that popularity does not determine truth. Science, itself, is full of such anecdotal counterexamples. Some of the most famous examples are those of the Scientific Revolution, where rebellious scientist-philosophers such as Galileo fought against the tide of commonly accepted 'truth' and won. If anywhere, science is where one can stand against the majority and emerge victorious and vindicated.
Looking even only briefly at the popular discussion of climate science, one quickly stumbles upon the oft-repeated argument of "There is a consensus of scientists who believe that climate change is real" to which the response is always "Science does not work by consensus!" If you're trying to explain how you know that climate change is real, the argument from consensus falls flat. The scientific method does not work by consensus. When a scientist is trying to determine how much Arctic sea ice has been lost during the summer melt this year, their answers come from the scientific evidence, not from assessing how much sea ice the majority of scientists believe has been lost. So, if you're going to argue about knowledge, you need to argue from the scientific evidence.
That all said, consensus does appear to play a role in the institution of scientific progress. My understanding of science as an advancing body of work and a congregation of like-minded investigators has been influenced by Thomas Kuhn's writings on scientific research paradigms. Kuhn, who was not without his detractors, argued that scientists are also humans bound by subjective biases which affect their scientific work. Although the Baconian scientific method does a spectacular job of focusing a scientist's work through a prism of objectivity, the work is still defined by the world view within which the scientist was trained. When the world view produces a theory which fails to explain fundamental phenomena, the world view slowly becomes challenged and eventually rejected. At this point, when a new paradigm and accompanying world view successfully arises, the consensus of scientific acceptance shifts appropriately. At this 'macro' level of science, consensus appears to play an important role. The world view is established by the consensus of scientists. When older scientists train younger scientists, the younger scientists are adopted into the consensus by being taught the world view of the older scientists.
This consensus is tested, however, when the world view is clearly plagued with inconsistencies of theory and experiment. But without this consensus, the scientific community could not function. The consensus of world view determines the terminology, methodology and even purpose of a particular scientific discipline. Without a consensus, scientists would be stuck arguing first principles and not actually performing any research. Scientists accept the consensus position, even if slightly flawed, in order to proceed with the dirty business of extending research. If the consensus position was too outrageous (e.g. if predictions clearly did not match the data) the consensus would be rejected and redrawn as a new paradigm. So while we can see that consensus does not play a role in the 'micro' level of scientific research, consensus does play a role in the 'macro' level of scientific progress. But I don't believe this level of acceptance of consensus in scientific paradigms constitutes anything fallacious or akin to 'groupthink' because scientists are trained (more than anybody else) to challenge the consensus. Consensus is accepted because it works.
When it comes to communicating climate science, however, consensus is an important talking point. Climate change is incredibly complicated. Climate scientists have known about climate change for decades and have understood the physics for over a hundred years. But only in the last decade or so has the public really started to catch onto this issue. Why? Other than political obstruction (which is a story for another day), the big issue seems to be the difficulty of communicating the science. Naturally, when a journalist has neither the time nor expertise to appropriately convey the complex science, an argument appealing to the trustworthy authority of the scientific majority is made instead. Is it fallacious? Yes. But is it fair? I think so. We should trust our scientists on complex issues concerning the health of our climate just as we would trust our doctors on complex issues concerning the health of our children.
1. An extremely high proportion of UFO researchers also believe that there is enough evidence of UFOs to justify their grant money. Climate researchers are no different. The more highly invested a researcher is in a particular field, they less they can be relied upon to objectively assess the underlying premise of the field.
ReplyDelete2. "Active climate researchers" includes scientists whose research begins from the premise of anthropogenic climate change. The overwhelming majority of papers published in the climate research field study the effects of anthropogenic climate change. Only a very small number of researchers actually tackle the question of the existence of anthropogenic climate change.
3. Prominence in a field is determined primarily by other researchers within a very small circle. When one's entire field relies on the existence of a certain phenomenon, challenges to this idea are unlikely to receive large numbers of citations. More so than in many fields, success in climate research is about agreeing with the right people.
I agree entirely with the points you make in the article. I think this is a fair and balanced representation of the idea of consensus science. However, I am personally a lot more skeptical of the motivations of the scientific community, and the robustness of the peer review process than you are (to the extent to which I have been able to infer such things from your post).
As a both shocking and hilarious example, I offer the following paper for your consideration:
http://care.diabetesjournals.org/content/17/2/152.abstract
Look at the number of citations. Clearly this author enjoys the respect of his peers. What's wrong with it? Read the abstract closely. (Hint: http://www.stat.columbia.edu/~cook/movabletype/archives/2010/12/reinventing_the.html)
Chris
P.S. Interesting blog. Added to my feed reader.
@chris
ReplyDelete1. Yes but UFO research does not show up in peer review scientific journals. A good scientist would not bias their research in search of their magic statement. A good scientist attempts to find the truth and if along the way the scientist makes a mistake someone will surely correct that mistake because crticising research is an important part of the peer review process.
2. There is plenty of interest in whether climate change exists and research most of these respected scientists (I cannot say all) will follow a rigourous objective approach. The evidence does show overwhelmingly of the affect humans are having on the environment.
3. There are plenty of scientists who attempt to prove the existence of climate change wrong those people critism is shown to be time and time again completely wrong. Success in the field is determined by doing good science and it just so happens that the good science sides with the facts which is that global antropogenic climate change is occuring.
July 7, 2011 5:29 PM
# Reposted for spelling corrections #
ReplyDelete1. "A good scientist would not bias their research in search of their magic statement."
This is true, but doesn't negate my point at all. A good researcher would indeed be objective. That doesn't imply anything at all about a given group of researchers.
2. "There is plenty of interest in whether climate change exists and research most of these respected scientists (I cannot say all) will follow a rigourous objective approach."
a. Interest from whom? I'm familiar with, I would venture to say, the vast majority of the published research in this area, and I can think of only a handful of researchers who have attempted to address this question seriously.
b. Respected by whom? Their fellow scientists, no doubt. The same scientists who reinforce their own beliefs by affirming the credibility of others who share them.
c. Do they follow a rigorous approach? You state it with conviction, yet it would be hard for anyone to say, given the flabbergasting reticence that some researchers have displayed in releasing their methods and data. While this practice is considered an integral part of the scientific process, increasingly climate researchers in particular are reluctant to release such vital information. The documented accounts of this are endless.
d. I completely disagree that the evidence is overwhelmingly in favour of a strong anthropogenic effect on the Earth's climate. What evidence there is weak, riddled with unaccounted-for uncertainty and sometimes the subject of outright scientific deceit. Furthermore, this ciriticism does not address my point.
3.
a. Actually, criticism from outside a select group of 'climate scientists' is systematically ignored. As but one among the multitude of such cases, Tiljander's sediment data is still being used as a proxy, despite the inversion by Mann et al. which Tiljander himself pointed out. This dataset has survived numerous rounds of the peer review process, despite being fatally flawed. Climate science is replete with such examples.
b. "Success in the field is determined by doing good science" - this is untrue for a great many fields, climate science being just one among many.
c. "it just so happens that the good science sides with the facts which is that global antropogenic climate change is occuring" - http://en.wikipedia.org/wiki/Begging_the_question
Chris
Nice analysis, Matt. However, in response to both you and the more skeptical Chris, above, I think you both miss the most important point of scientific inquiry on climate, which is that this science is supported not only by a nearly unanimous consensus of climatologists but also by majorities of scientists working in many related disciplines such as physics, paleontology, biology, geology, oceanography, glaciology and so on. The science is not the result of a narrow line of inquiry; it is the product of many researchers across numerous fields.
ReplyDelete