How the Scientific Consensus Can Be Wrong

Consensus is a necessary step on the road from scientific hypothesis to theory. What many people don’t realize, however, is that a consensus isn’t necessarily the last word. A consensus, whether newly proposed or well-established, can be wrong. In fact, the mistaken consensus has been a recurring feature of science for many hundreds of years.

A recent example of a widespread consensus that nevertheless erred was the belief that peptic ulcers were caused by stress or spicy foods – a dogma that persisted in the medical community for much of the 20th century. The scientific explanation at the time was that stress or poor eating habits resulted in excess secretion of gastric acid, which could erode the digestive lining and create an ulcer.

But two Australian doctors discovered evidence that peptic ulcer disease was caused by a bacterial infection of the stomach, not stress, and could be treated easily with antibiotics. Yet overturning such a longstanding consensus to the contrary would not be simple. As one of the doctors, Barry Marshall, put it:

“…beliefs on gastritis were more akin to a religion than having any basis in scientific fact.”

To convince the medical establishment the pair were right, Marshall resorted in 1984 to the drastic measure of infecting himself with a potion containing the bacterium in question (known as Helicobacter pylori). Despite this bold and risky act, the medical world didn’t finally accept the new doctrine until 1994. In 2005, Barry Marshall and Robin Warren were awarded the Nobel Prize in Medicine for their discovery.

Earlier last century, an individual fighting established authority had overthrown conventional scientific wisdom in the field of geology. Acceptance of Alfred Wegener’s revolutionary theory of continental drift, proposed in 1912, was delayed for many decades – even longer than resistance continued to the infection explanation for ulcers – because the theory was seen as a threat to the geological establishment.

Geologists of the day refused to take seriously Wegener’s circumstantial evidence of matchups across the ocean in continental coastlines, animal and plant fossils, mountain chains and glacial deposits, clinging instead to the consensus of a contracting earth to explain these disparate phenomena. The old consensus of fixed continents endured among geologists even as new, direct evidence for continental drift surfaced, including mysterious magnetic stripes on the seafloor. But only after the emergence in the 1960s of plate tectonics, which describes the slow sliding of thick slabs of the earth’s crust, did continental drift theory become the new consensus.

A much older but well-known example of a mistaken consensus is the geocentric (earth-centered) model of the solar system that held sway for 1,500 years. This model was originally developed by ancient Greek philosophers Plato and Aristotle, and later simplified by the astronomer Ptolemy in the 2nd century. Medieval Italian mathematician Galileo Galilei fought to overturn the geocentric consensus, advocating instead the rival heliocentric (sun-centered) model of Copernicus – the model which we accept today, and for which Galileo gathered evidence in the form of unprecedented telescopic observations of the sun, planets and planetary moons.    

Although Galileo was correct, his endorsement of the heliocentric model brought him into conflict with university academics and the Catholic Church, both of which adhered to Ptolemy’s geocentric model. A resolute Galileo insisted that:

 “In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual.”

But to no avail: Galileo was called before the Inquisition, forbidden to defend Copernican ideas, and finally sentenced to house arrest for publishing a book that did just that and also ridiculed the Pope.

These are far from the only cases in the history of science of a consensus that was wrong. Others include the widely held 19th-century religious belief in creationism that impeded acceptance of Darwin’s theory of evolution, and the 20th-century paradigm linking saturated fat to heart disease.

Consensus is built only slowly, so belief in the consensus tends to become entrenched over time and is not easily abandoned by its devotees. This is certainly the case for the current consensus that climate change is largely a result of human activity – a consensus, as I’ve argued in a previous post, that is most likely mistaken.

Next: Nature vs Nurture: Does Epigenetics Challenge Evolution?

How Elizabeth Holmes Abused Science to Deceive Investors

Even in Silicon Valley, which is no stranger to hubris and deceit, it stands out – the bold-faced audacity of a young Stanford dropout, who bilked prominent investors out of hundreds of millions of dollars for a fictitious blood-testing technology based on finger-stick specimens.

Credit: Associated Press

Elizabeth Holmes, former CEO of now defunct Theranos, last year settled charges of massive financial fraud brought by the U.S. SEC (Securities and Exchange Commission), and now faces criminal charges in California for her multiple misdeeds. But beyond the harm done to duped investors, fired employees and patients misled about blood test results, Holmes’ duplicity and pathological lies only add to the abuse being heaped on science today.

One of the linchpins of the scientific method, a combination of observation and reason developed and refined for more than two thousand years, is the replication step. Observations that can’t be repeated, preferably by independent investigators, don’t qualify as scientific evidence. When the observations are blood tests on actual patients, repeatability and reliability are obviously paramount. Yet Theranos failed badly in both these areas.

Holmes created a compact testing device originally known as the Edison and later dubbed the minLab, supposedly capable of inexpensively diagnosing everything from diabetes to cancer. But within a year or two, questions began to emerge about just how good it was.

Several Theranos scientists protested in 2013 that the technology wasn’t ready for the market. Instead of repeatable results, the company’s new machine was generating inaccurate and even erroneous data for patients. Whistleblowers addressing a recent forum related how open falsification and cherry-picking of data were a regular part of everyday operations at Theranos. And technicians had to rerun tests if the results weren’t “acceptable” to management.

Much of this chicanery was exposed by Wall Street Journal investigative reporter John Carreyrou. In the wake of his sensational reporting, drugstore chain Walgreens announced in 2015 that it was suspending previous plans to establish blood testing facilities using Theranos technology in more than 40 stores across the U.S.

Among the horrors that Carreyrou documented in a later book were a Theranos test on a 16-year-old Arizona girl, whose faulty result showed a high level of potassium, meaning she could have been at risk of a heart attack. Tests on another Arizona woman suggested an impending stroke, for which she was unnecessarily rushed to a hospital emergency room. Hospital tests contradicted both sets of Theranos data. In January 2016, the Centers for Medicare and Medicaid Services, the oversight agency for blood-testing laboratories, declared that one of Theranos' labs posed "immediate jeopardy" to patients.

Closely allied to the repeatability required by the scientific method is transparency. Replication of a result isn’t possible unless the scientists who conducted the original experiment described their work openly and honestly – something that doesn’t always occur today. To be fair, there’s a need for a certain degree of secrecy in a commercial setting, in order to protect a company’s intellectual property. However, this need shouldn’t extend to internal operations of the company or to interactions between the very employees whose research is the basis of the company’s products.

But that’s exactly what happened at Theranos, where its scientists and technicians were kept in the dark about the purpose of their work and constantly shuffled from department to department. Physical barriers were erected in the research facility to prevent employees from actually seeing the lab-on-a-chip device, based on microfluidics and biochemistry, supposedly under development.

Only a handful of people knew that the much-vaunted technology was in fact a fake. In a 2014 article in Fortune magazine, Holmes claimed that Theranos already offered more than 200 blood tests and was ramping up to more than 1,000. The reality was that Theranos could only perform 12 of the 200-plus tests, all of one type, on its own equipment and had to use third-party analyzers to carry out all the other tests. Worse, Holmes allegedly knew that the miniLab had problems with accuracy and reliability, was slower than some competing devices and, in some ways, wasn’t competitive at all with more conventional blood-testing machines.

Investors were fooled too. Among the luminaries deceived by Holmes were former U.S. Secretaries of State Henry Kissinger and George Shultz, recently resigned Secretary of Defense and retired General James Mattis – all of whom became members of Theranos’ “all-star board” – and media tycoon Rupert Murdoch. Initial meetings with new investors were often followed by a rigged demonstration of the miniLab purporting to analyze their just-collected finger-stick samples.

Holmes not only fleeced her investors but also did a great disservice to science. The story will shortly be immortalized in a movie starring Jennifer Lawrence as Holmes.

Next: How the Scientific Consensus Can Be Wrong