A couple of years ago I heard Al Gore on a radio program in New York City. On the program, the announcer and Gore engaged in hysteria as well as misapplication of the concept of science. The left has long claimed to represent the "educated" point of view but has consistently refused to face facts and has consistently avoided to apply the principles on which science is based to its own ideas. It is therefore accurate to say that the ideas that appear in the New York Times are not representative of the views of educated or enlightened people but rather of fanatical cranks.
Global warming well illustrates this principle, although the attitudes of the cranks toward socialism, urban renewal, centralized economic planning, economic regulation, welfare, taxation and a host of other issues on which they insist on views that contradict available evidence would serve equally well.
This morning a reader named B Van Gerven raised this question on my blog concerning global warming. I had blogged that the Al Gore/man-made global warming enthusiasts do not engage in science because they refuse to state a basis on which the claim that the world is getting warmer can be proven false. In fact, the world has not been getting warmer for the past couple of years, and a German scientist has offered a contending theory about the effects of oceanic phenomena on climate that would suggest a period of global cooling. The reader claims:
>The AGW theory is not falsifiable. Many perfectly valid scientific theories are not falsifiable, f.i. “Smoking increases the risk of getting lung cancer” is a statement that is not falsifiable, but I think few scientists – and ordinary people – will doubt that it is true.
>A scientific theory is is generally accepted by the scientific community, not because it hasn’t been falsified, but because it explains and predicts very well the phenomena that occur.
As I responded to the reader, the claim that (a) because scientists believe something then (b) they are engaging in science fails to accurately depict what science is. B Van Gerven is incorrect that the claim that smoking causes cancer is not falsifiable. It certainly is. Karl Popper's "Logic of Scientific Discovery" outlines the meaning of the term "falsifiable". Peter Blau, the famous Columbia University sociologist of the 1950s-1980s introduced me to this concept when I took his sociological theorizing course in 1988, right before he retired.
Van Gerven expresses a common misconception of how science ought to work. A scientific theory doesn't necessarily predict phenomena. For example, the astronomical theories of cosmology and cosmogony as well as archaeology and biology, anatomy and many other disciplines do not make predictions. Very little in the social sciences makes predictions. Economics, for instance, is incapable of making predictions beyond the most general and long term level. It can predict that more money will cause inflation, but it cannot predict how much inflation or when or whether given that all things are not held equal what will happen.
Popper defines falsifiability as the use of evidence to contradict theory. That is, in fact, how science works. Theories can never be proven true, they can only be proven false or falsified.
In the case of smoking, falsifiability works like this. A scientist states the hypothesis that smoking causes cancer. Data are collected. The data show that smokers, controlling for all other determinable variables, die sooner, have higher rates of heart attacks and the like. This is consistent with the hypothesis. But this evidence does not "prove" the hypothesis because the researcher may have omitted controls. Theories are never finally proven.
Let us say that a study found that if one controls for sun spots, then the significance of the smoking factor disappears. That would falsify the smoking hypothesis. Smoking-causes-cancer theorists then have to show that the sunspot factor does not dominate the smoking factor. If several studies found that sun spots dominate the smoking effect, then the smoking factor would be falsified.
As Thomas Kuhn shows in his classic "Structure of Scientific Revolutions" science moves to new paradigms not because of the absolute falsehood of the old paradigm but because of the old paradigm's inability to explain contradictions.
Knowledge in the layman's sense is not science. You know that when a sign says "Trenton" that if you take the exit you are likely to arrive at points south if you are leaving New York City. But that is not science. Aristotle believed that appearances lead to knowledge, and he was right, in my opinion, with respect to human decision making. It becomes evident as you examine data in depth that it is extraordinarily hazardous to say anything with certainty. The scientific mind is a questioning mind.
As Popper points out, science depends on falsifiability because scientists must always be open to the possibility that they are wrong. In true science, contradictions inevitability appear as data are adduced. Theories lend order to observed data, but are never complete. As contradictions accumulate, new models are proposed. If the process of academic science inhibits the introduction of new models excessively, then it is inhibiting science. It is true that "normal science" makes greater progress than revolutionary science, so it is generally the case that paradigm shifts are few and far between. But with respect to a theory like global warming that has little evidence, insisting on its accuracy without considerable review is not science.
The claim that science is "settled" is inherently anti-scientific, as a reading of Popper and Kuhn will clearly show. In the case of global warming, it is not merely anti-scientific but reflective of a displacement of science by politics. It is similar to the claim of Trofim Lysenko in the Sovient Union that acquired characteristics are inheritable. Although science has falsified this claim, the Soviet government enforced it, throwing into prison any who disagreed with it. American leftists follow a similar strategy of their Soviet role models and insist on the valididity of a theory that lacks credibility, saying that it is "settled".
The scientific community's acceptance of theory is meaningful only to a point. Unless contradictions are being reconciled to the theory, then the risk of scientism and fanaticism appears. This is the case of global warming theory, where scientists, eager for grants and political acceptance, have played to the mob, debasing their claim to legitimacy. The recent discovery of e-mails attesting to my claim made early last year, suggests that a large part of the geological community is a disgrace.
