"Settled"

The contribution of scientific experts to a health crisis:

Anyone who thinks it’s enough to rest an argument on “settled science” or a “scientific consensus” ought to read about John Yudkin.
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“At best, we can conclude that the official guidelines did not achieve their objective; at worse, they led to a decades-long health catastrophe,” Leslie writes.

Nutritionists are only now grudgingly beginning to admit that their approach to nutrition guidelines could have been, well, wrong, and Yudkin’s work is only now being rediscovered.
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So why didn’t scientists wise up sooner?

Leslie correctly points out that, despite the patina of pure objectivity, “scientific inquiry is prone to the eternal rules of human social life: deference to the charismatic, herding toward majority opinion, punishment for deviance, and intense discomfort with admitting to error.”

That’s not to say the scientific method doesn’t eventually correct these errors, but the process isn’t fast or painless.
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 Yudkin’s plight should be a cautionary tale to anyone who thinks we should blindly follow a scientific consensus, particularly when it involves extraordinarily complex entities like the human body, or when the consensus is used to push public policies that could affect vast populations.

Then there is the consensus du jour about climate:

Authoritarianism, always latent in progressivism, is becoming explicit. Progressivism’s determination to regulate thought by regulating speech is apparent in the campaign by 16 states’ attorneys general and those of the District of Columbia and the Virgin Islands, none Republican, to criminalize skepticism about the supposedly “settled” conclusions of climate science. 

Four core tenets of progressivism are: First, history has a destination. Second, progressives uniquely discern it. (Barack Obama frequently declares things to be on or opposed to “the right side of history.”) Third, politics should be democratic but peripheral to governance, which is the responsibility of experts scientifically administering the regulatory state. Fourth, enlightened progressives should enforce limits on speech (witness IRS suppression of conservative advocacy groups) in order to prevent thinking unhelpful to history’s progressive unfolding.

Progressivism is already enforced on campuses by restrictions on speech that might produce what progressives consider retrograde intellectual diversity. Now, from the so-called party of science, a.k.a. Democrats, comes a campaign to criminalize debate about science.

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The party of science, busy protecting science from scrutiny, has forgotten Karl Popper (1902–94), the philosopher whose The Open Society and Its Enemies warned against people incapable of distinguishing between certainty and certitude. In his essay “Science as Falsification,” Popper explains why “the criterion of a scientific status of a theory is its falsifiability, or refutability, or testability.” America’s party of science seems eager to insulate its scientific theories from the possibility of refutation.
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These garden-variety authoritarians are eager to regulate us into conformity with the “settled” consensus du jour, whatever it is. But they are progressives, so it is for our own good.

There is nothing wrong with some boldness in believing that knowledge can be advanced by scientific inquiry.  It is however, wise to have substantial humility about the chance for error and the difficulty of error correction in such matters.  This is extremely important when it comes to using such knowledge in the field of public policy.

update: Victor Davis Hanson provides a valuable contribution in The Myth of Progress

President Obama is fond of using the phrase “the arc of the moral universe,” a line derived from Martin Luther King Jr’s longer quote, “The arc of the moral universe is long but it bends toward justice.”

King, in fact, lifted the often-used sentence from earlier Christian ministers. They, in turn, apparently borrowed the optimistic adage from its originator, Theodore Parker, a mid-nineteenth-century transcendentalist preacher. Obama also frequently favors sayings such as “the right side of history” and “the wrong side of history,” even though these Marxist nuggets refer to the supposed inevitable and morally overdue triumph of statism. Another favored presidential expression is “settled science,” as if natural inquiry always meets the end of history and becomes frozen in amber.

There is an underlying theme in these expressions of President Obama: predetermination. When expressing and implementing his views on government services, taxes, social awareness, racial relations and diversity, gay marriage, foreign policy, or global warming, the president often seeks refuge in the notion that cosmic forces both agree with him and are unimpeachable. As a consequence, further debate is futile. Sophisticates understand that finality; rubes do not.

Let’s take his “settled science” claim first. Unfortunately equating a current preponderance of transitory scientific opinions with eternal truth is precisely the way science does not work. There are some absolute truths in science, like the laws of atomic weight, but much else is up for debate and exploration. The etiology of ulcers and the effects of sunlight on the skin are explained differently today than they were in 1980—and perhaps will be explained differently still in 2080.

Most landmark breakthroughs in any field are not the product of consensus, but the unanticipated work of lone wolves, who were once derided as feral outliers barking at the moon. Had Obama used his majority arguments for settled science against Nicolaus Copernicus, Galileo Galilei, Sir Isaac Newton, and Charles Darwin, we might believe that the earth was created 5,000 years ago, gravity did not exist, and the planets revolved around the earth.
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 “Settle science” became a synonym for progressive dialectics. Obama never references settled science in reference to groups statistically most likely to suffer from hate crimes, or to commit acts of terrorism, or to commit felonies and murders inordinately given their numbers in the general population, or to scientific studies concerning the lack of climate impact from building the Keystone Pipeline, or the proven remedies for California drought relief through additional dams, reservoirs, and canals.
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What does the president also mean by the “right” and “wrong” side of history, other than equating his side with “right” and thus historically, morally, and logically inevitable? But history has no such predetermined Hegelian course. Roman republicanism and classical culture were certainly on the right side of history for centuries—until life in AD 500 insidiously became far more dangerous, brutish, and materially impoverished. Beheading was supposed to be the signature of past savages, not the highlight of twenty-first-century video ads for ISIS recruitment.
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Certainly “the arc of the moral universe” may be long, but unfortunately I’m not sure it bends in any particular direction. 
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And we forget that technological progress can often accompany moral regress—a favorite classical topos from the early Greek poet Hesiod to the Roman elegist and satirist Horace. The gas chambers of the Holocaust were fueled by the most sophisticated cyanide-based pesticide—Zyklon B—that pathbreaking German chemists could concoct. And the crematoria of the death camps were proudly stamped with the trademark “Topf and Sons,” a benchmark of German excellence in the engineering of waste removal.

Nor is there reason to believe that the arc of history bends toward diversity, however noble the sentiment. Prosperous China, Japan, and South Korea have never shared much trust in such ethnic and racial ecumenicalism.
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 The classical world did not believe in linear progressions, but rather in cyclical ones, often using the metaphor of human birth, aging, and death as a natural referent. Cultures and nations start out in diapers like babies and often end in them too—as do aged humans.
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 Human nature stays constant as the material world continually transforms. People are not pawns of history or pilgrims skipping up some radiant celestial arc. Sometimes the people, ideas, and movements of the twenty-first century prove better, and sometimes far worse, than those of the past—and they will likewise again when framed against the future.

Human capacity for creativity is truly amazing but so is the willingness to embrace follies such as scientism and historicism.