Twitter has a new policy concerning tweets: “Misleading advertisements on #Twitter that contradict the scientific consensus on #climatechange are prohibited, in line with its inappropriate content policy.”

The word pairing “scientific consensus” used in this policy is a destructive science-stifling oxymoron.

Michael Crichton (1942–2008) would surely have said so. Crichton was the author of wonderful science fiction, including Jurassic Park. and The Andromeda Strain. In a lecture at Caltech, the late master story teller gave Twitter’s policy a gut punch:

Historically, the claim of consensus has been the first refuge of scoundrels; it is a way to avoid debate by claiming that the matter is already settled. Whenever you hear the consensus of scientists agrees on something or other, reach for your wallet, because you’re being had.

Let’s be clear: the work of science has nothing whatever to do with consensus. Consensus is the business of politics. Science, on the contrary, requires only one investigator who happens to be right, which means that he or she has results that are verifiable by reference to the real world. In science consensus is irrelevant. What is relevant is reproducible results. The greatest scientists in history are great precisely because they broke with the consensus. There is no such thing as consensus science. If it’s consensus, it isn’t science. If it’s science, it isn’t consensus. Period.”

Michael Crichton, “Aliens Cause Global Warming” at Caltech Michelin Lecture, January 17, 2003

Claims of scientific consensus often lead to ultimate embarrassment. Take, for example, Professor Peter Gunter who, in 1970, defended an alarming claim with an appeal to consensus:

Demographers agree almost unanimously on the following grim timetable…. By the year 2000, or conceivably sooner, South and Central America will exist under famine conditions…. By the year 2000, thirty years from now, the entire world, with the exception of Western Europe, North America, and Australia, will be in famine.

There have been famines since Gunter’s prophesy. But they sporadically occur locally due to droughts, war and politics. Gunter’s appeal to global famine was wrong and he will be primary remembered in history for wrongness of his consensus-based claim.

Some who bucked scientific consensus have made world-changing discoveries. Here’s one. For a long time the medical consensus was that peptic ulcers were caused by stress and lifestyle factors. Two Australian researchers, however, came to believe ulcers were caused by bacteria. Barry J. Marshall and Robin Warren’s claim was so far outside of consensus that no scientist believed them.

To prove the theory, Marshall underwent a gastric biopsy to demonstrate that he had no ulcer. Then he infected himself with bacteria and formed an ulcer. When he cured himself with antibiotics and bismuth salt regimens his theory was proved. Marshall’s dedication to disproving consensus was, as they say, beyond the call. Marshall and Warren were awarded a Nobel Prize for ignoring scientific consensus and thinking and acting creatively outside the box.

Or take Albert Einstein, who at the tender age of twenty-six challenged consensus in his development of relativity. For one thing, the speed of light was widely viewed to be relative to the speed of the observer with respect to the light source. Motivated by the Michelson-Morley experiment, Einstein abandoned this consensus. He theorized the speed of light was a constant independent of the relative speeds of the light source and the observer. Further, it was (correctly) understood that sound waves need air or some other media to propagate. Scientists during the time of Einstein believed electromagnetic waves like light need some similar media in outer space and assumed something called aether was the propagation media. Einstein correctly hypothesized there was no aether. Based on going out-of-the-box of consensus, the theory of relativity was born.

So by appealing to “scientific consensus” on climate change, Twitter is roping off sections in the arena of ideas. I don’t claim to know the answer. But I do know that by limiting dialog and censoring minority scientific viewpoints, Twitter helps keep our spinning wheels stuck in the mud on the road to potential progress.

Twitter should abandon consensus policies, allow iron to sharpen iron and quit being one of Crichton’s scoundrels.

You may also wish to read:

Consensus gives us information only if we are free to doubt. As a recent paper shows, both influence and coercion mathematically reduce the value of a consensus. Using Bayes’ theorem, the researchers found that, real without freedom to dissent, an expert consensus can easily form around a false idea. (Jonathan Bartlett)