Monday, May 5, 2008

It's a Political Neologism: The Problem with "Consensus" Science

I have been thinking about writing this entry for at least a month.
And I have shied away from it because of the flaming I will probably receive
from the BSer ideologues of the blogosphere, but I remembered this little quote:

"He said: 'G-d hates a coward.'
'So you came because you didn't want to lose a bet?'
"No. I would never bet on a lady. I just figured that he was right.'"
(This may be slightly paraphrased. I read the book in fourth grade. Many HSers will know which book).

My other excuses are gone: I have finished three papers, an exam, and an NIH draft proposal.
And even though I am in training for my summer job, and that is quite extensive, it does not take the same intellectual energy that writing closely argued papers about big ideas does.

I want to start with a story.

At the beginning of the last century, a geologist in Germany called Alfred Wegener went for a walk on a spring day and got caught up watching the ice break up on the river. As he did so, he was thinking about the interesting fact that similar fossils from similar strata were found on different continents. The ice breaking up in the river was one of those "aha" moments, and he said something akin to "Eureka! I have found Pangea!" (My apologies to Archemedes). He wrote extensively about his idea of Continental Drift and he even developed a mechanism for it--that centrifugal force caused the continents to drift about the planet. But that mechanism was not very plausible, and he was ridiculed severely by his fellow geologists. Wegener did not live to see the modern scientific revolution in the Earth Sciences resulting in the paradigm of Plate Tectonics.

Were Wegener's colleagues defenders of "consensus" science? This idea has been recently bandied about by those who have a bone to pick with Global Climate Change (often inaccurately called "global warming").

The answer is no. Although the ridiculing of Wegener was over the top,
inpolite, and generally shows that many scientists lack the social graces, a characteristic they share with the rest of humanity,
this has nothing to do with why his idea was rejected back at the beginning of the 20th century. His idea was rejected because, although he had a good deal of circumstantial evidence (fossils of ferns in Antarctica, the shape of South America and Africa), he could demonstrate no plausible mechanism for his theory. It was not exactly a crack-pot idea--it had possibilities--but it was also not scientifically defendable at the time. It was not until the International Geophysical Year of 1956 brought about a decade of accumulating evidence that the old paradigm (geosynclinal) could not explain, that a good mechanism for continental drift was found, and the theory of Plate Tectonics was born.

Scientists do not generally speak in terms of "consensus" in their fields.
This is not because there is none--most working scientists do work under the dominant paradigm in their fields (such as evolutionary theory in biology)--but because scientific questions are not decided by consensus. They are decided by evidence that supports a theory or not.

Scientific paradigms do not change just because a bunch of scientists get together in smoke filled rooms and decide that they are tired of the old paradigm and they'd like to trade it in for a new one, like an old-model car. A paradigm shift is not brought about by a vote or political pressure by concerned citizens. It is not created because someone goes on a fishing expedition to disprove an unpopular idea. Neither is one caused by a few crusaders for scientific truth battling it out with the forces of complacency and the need to get NSF grants and media coverage.

Scientific paradigms shift because of the accumulation of evidence by many people working in the field, (most of whom are not out to create a scientific revolution), evidence that does not support the current theory. Consensus, for good or ill, has nothing to do with it. Science does not work that way. And contrary to popular belief, the inception of a new paradigm does not automatically cast the old one into the outer darkness of scientific untruth. Bohr and Einstein (Quantum Mechanics) did not, for example, overturn Newton (Classical Mechanics). Newton's laws are still with us and they still work. Don't go to Mars without them!

Consensus is a social phenomenon and a political term.
It is about getting together and hammering out a deal that everyone in an argument can agree to, even if they don't like all of the parts of it.
One cannot hammer out a deal about gravity, or the duel nature of light (particle and wave), or the role of the electron in chemical reactions. One cannot vote the theory of evolution up or down.
Consensus is simply not a scientific term.

So when I see the term 'consensus science' bandied about in the press, among pols, and in common parlance, I know that the discussion is not a scientific one.
I know the discussion has become political.

Take Global Climate Change (GCC)--please! (Sorry. I just had to do that. It's in my genes ;).
There is little question that the earth's climate has changed over the 4.6 billion years of its existence. It is not surprising that climate has continued changing even though humanity has built civilization over the past 10,000 years. (Oh the temerity of nature! Oh, the duplicity of nature's God! How dare this happen just now, when the Boomers are in charge)!

Scientific questions about GCC center on how it is changing, what modeling procedures give the best predictions for future change, what forces intensify or mitigate the change, how the change will affect weather in different localities and so forth. All of these questions involve factors of great complexity and are hotly debated, and rightly so. The scientific controversy is over the evidence and what it tells us.
There should be no premature closure on questions like these because "four out of five scientists say so." Science is not done by taking polls.

The politics of GCC is, as we used to say in the midwest, "a whole 'nother animal."
Questions of a political nature about GCC are, for example, what (if anything) should we do about GCC, can and should we try to alter its course (to which I say sardonically, "Good luck!"), who should be blamed, and how can GCC be "spun" in order to fit a favorite political ideology.

Science does not work by consensus.
When you see the term "consensus science" used,
your gut should be telling you that the discussion has gone political.
Whether it is used to promote Carbon Credits, or demand equal time for Intelligent Design,
matters not. The right, the left, the rigid and the looney, are all equally guilty of hijacking the term "science" to promote their own political ends.

Science is a method of discovering how the physical world works through the use of physical evidence. It cannot tell us what to believe about supernatural beings, nor can it tell us the best way to deal with the current price of oil.

Consensus science?
Science is science.
The arguments about consensus a la Al Gore and Ben Stein are political.

1 comment:

Amie said...

Good post. Right on.