Science is a method of organizing our curiosity.
—TIM MINCHIN, AUSTRALIAN COMEDIAN, ACTOR, AND MUSICIAN
Science delivered us out of the Age of Darkness and into the Age of Enlightenment.
Three hundred years ago, graveyards overflowed with small, white coffins. Children died from smallpox, meningitis, pneumonia, whooping cough, bloodstream infections, scarlet fever, diphtheria, hepatitis, measles, and food poisoning. Of every hundred children born, twenty would be dead before their fifth birthday. Mothers died from tuberculosis and childbed fever. Crop failures led to famines and starvation. Homes were infested with filth and vermin. The average life span was thirty-five years.
Scientific advances have eliminated most of this suffering and death. Vaccines, antibiotics, sanitation programs, pest control, synthetic fertilizers, X-rays, air conditioning, recombinant DNA technology, refrigeration, and pasteurization—to name just a few—have allowed us to live longer, better, healthier lives. During the last hundred years alone, the life span of Americans has increased by thirty years.
Unfortunately, scientific discoveries have a darker side. Physicists have given us atomic bombs, which, in 1945, were dropped on civilian populations in Hiroshima and Nagasaki, killing more than one hundred thousand people. Chemists have given us opioids like heroin and fentanyl, which kill about sixty thousand Americans every year. And, through what are called gain-of-function studies, biologists have invented ways to make deadly viruses and bacteria even more contagious; these new microbes have the capacity to cause plagues more devastating than anyone has ever encountered.
The fear that our reach has exceeded our grasp is reflected in movies like Frankenstein (1931), Colossus: The Forbin Project (1970), Westworld (1973), Jurassic Park (1993), 28 Days Later (2002), Splice (2009), and Ex Machina (2015), each depicting a world in which science is out of control—something to fear, not embrace. “Our scientific power has outrun our spiritual power,” said Martin Luther King Jr. “We have guided missiles and misguided men.”
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LET’S START BY TAKING A STEP BACK AND ASKING A BASIC QUESTION: What is science?
Stripped to its essence, science is simply a method to understand the natural world—it’s an antidote to superstition.
In a sense, everyone is a scientist. For example, if a car doesn’t start, a mechanic considers several possibilities: the battery is dead; the starter is defective; the car is out of gas; the fuel system is clogged. Then, the mechanic tests each of these potential problems. This is exactly how scientists think: hierarchically, reasonably, logically. It would be unreasonable to think that the car doesn’t start because the gods were angry or because the owner had cheated on his taxes. That’s not scientific thinking; that’s magical thinking. And it’s at the heart of a lot of misconceptions about how the world works and whether one thing causes another.
By far the most important part of the scientific process is reproducibility. If a scientist’s hypothesis is right, then other investigators will confirm that it’s right. If it’s wrong, they won’t. The beauty of science is that it’s enormously self-correcting, questioning, probing, skeptical, mutable. Nothing is a fact until it’s reproduced again and again and again.
It will probably come as a surprise to learn what science isn’t—it isn’t scientists or scientific textbooks or scientific papers or scientific advisory bodies. As once-cherished hypotheses are disproved, scientists throw away their textbooks without remorse. For some people, this is unnerving. We want certainty, especially when it comes to our health. And that’s when we get into trouble—what I’ll call the “Bones McCoy seduction.”
In the long-running television series Star Trek, Dr. Leonard H. “Bones” McCoy was the chief medical officer aboard the USS Enterprise. To make a diagnosis, McCoy briefly scanned the patient with a hand-held device called a tricorder. He then carefully examined the read-out. And that was it. If the scanner displayed a particular diagnosis, then that was the diagnosis. No questions. No doubts. This kind of certainty is attractive. And it’s why doctors like Mehmet Oz and Deepak Chopra, who often represent themselves as all-knowing gurus, are so seductive. They, too, express only certainty. They, too, know the truth, and their truth is immutable, fixed. Unfortunately, medical science doesn’t work that way; we’ll know much more in a hundred years than we know now. Nevertheless, when our health is at stake, it’s hard to accept that our knowledge is incomplete.
But take heart—scientific truths do emerge. Sometimes they emerge over months, sometimes years, and sometimes decades. But they do eventually emerge. And when these truths emerge, they become immutable. Evolution and climate change, for example, are no longer opinions; they’re facts built on a mountain of evidence.
Although we should trust the scientific process, we should be skeptical of scientists. Scientists get it wrong all the time. But if they’re wrong, they’ll eventually be shown to be wrong. There’s no hiding. For example:
• In 1926, Johannes Fibiger, a Danish scientist, won the Nobel Prize for his discovery of a worm he called Spiroptera carcinoma, which he believed caused cancer. Fibiger was an instant hero. At last, the cause of cancer had been found. But Fibiger was later proven wrong. Worms don’t cause cancer.
• In 1935, Egas Moniz, a Portuguese neurologist, won the Nobel Prize for inventing a surgical cure for anxiety, paranoia, schizophrenia, and bipolar disorder. He called his technique a leucotomy; when it crossed the Atlantic Ocean, it was called a lobotomy. The New York Times hailed Moniz as a “brave explorer of the human brain.” Over the next three decades, more than forty thousand lobotomies were performed across the globe, twenty thousand in the United States alone. But lobotomies didn’t cure anything. Rather, they caused memory loss, seizures, and, occasionally, fatal, uncontrollable bleeding. By the 1970s, lobotomies were relegated to the dusty bin of discarded psychiatric therapies, next to whips, chains, and snake pits.
• In 1957, the American physiologist Ancel Keys published a paper claiming that people who consumed less fat had a lower incidence of heart disease, coining the term “heart-healthy diet.” Keys was a well-respected scientist, a best-selling author, and a consultant to the World Health Organization and the United Nations. In 1961, he even appeared on the cover of Time magazine. When Ancel Keys gave advice, people listened. Because of Keys, margarine, which contained partially hydrogenated vegetable oils, became the “heart-healthy” alternative to butter, which contained animal fats. Although he didn’t realize it at the time, Keys had driven Americans into the waiting arms of trans fats. Four decades later, the Harvard School of Public Health estimated that trans fats were causing about two hundred fifty thousand heart-related deaths every year.
• In 1981, after interviewing more than four hundred people, Brian MacMahon concluded that excess coffee drinking increased the risk of pancreatic cancer. MacMahon, a researcher at the Harvard School of Public Health, published his findings in one of the most prestigious medical journals in the world, the New England Journal of Medicine. However, other scientists couldn’t find what MacMahon had found. And the notion that coffee enthusiasts risked a universally fatal cancer faded away.
• In 1989, Stanley Pons and Martin Fleischmann, nuclear physicists at the University of Utah, made a startling announcement. They claimed that they had created energy in a test tube by fusing two small nuclei to form a larger one. This was big news. Nuclear fusion occurs every day on the sun, the Earth’s greatest source of energy. But Pons and Fleischmann had created the sun’s energy at room temperature, providing a clean, inexpensive, and limitless source. They called their discovery “cold fusion.” Utah legislators were so proud of this homegrown breakthrough that they allocated $4 million to establish the National Cold Fusion Institute on the University of Utah’s campus. When more than seventy other research teams failed to find what Pons and Fleischmann had found, the hope of cold fusion died a quiet death. The building that once housed the National Cold Fusion Institute still stands, a literal monument to irreproducible science.
Some people hear stories like this and say, “See! That’s why you can’t trust science. Science gets it wrong all the time.” But they’re confusing science with scientists. While scientists might have certain biases—and doggedly stick to those biases—the scientific process prevails. Lobotomies, cold fusion, cancer-causing worms, and margarines loaded with trans fats didn’t stand the test of time. In other words, while it is reasonable to be skeptical of scientists, it is unreasonable to be skeptical of the scientific process.
In each of these stories, the scientific method won out. But until it did, the public was misled and confused. The reason was simple. Although scientists claim, correctly, that it’s all about the data, scientific data don’t speak for themselves. Someone has to speak for them. Of all the lessons I’ve had to learn, this one has probably been the hardest.
I’ll give you a specific example.
A few years ago, Amy Pisani, the executive director of Every Child By Two, a vaccine advocacy group, asked me to speak to Tom Harkin, the popular Democratic senator from Iowa. Harkin had requested that $2 million of the budget of the Centers for Disease Control and Prevention (CDC) be set aside to determine whether vaccines were causing developmental disabilities. Every Child By Two had been founded by the former first lady Rosalynn Carter and by Betty Bumpers, wife of the longtime senator Dale Bumpers. For the previous thirty years, these women had worked tirelessly to ensure that all children in the United States had access to the vaccines that could save their lives. In the wake of Senator Harkin’s request, Amy Pisani, Betty Bumpers, and I traveled to Washington, DC, to try to talk him out of it.
At the time, about two dozen studies had already examined the relationship between vaccines and developmental disabilities, including autism. My role in this meeting was to explain the power of these studies—to reassure Senator Harkin that what he was proposing to study had already been studied. Harkin was pleasant and affable, and he asked thoughtful questions. The only interaction during the meeting that unnerved me occurred as we were leaving.
Amy Pisani and Betty Bumpers left before I did, each shaking Senator Harkin’s hand. I, too, shook his hand and thanked him. But he didn’t let go. While holding my hand, he said that a group of scientists had visited him the previous week and said exactly the opposite of what I had just said. Who was he supposed to believe? I told him that it didn’t matter what they said or what I said. The only thing that mattered was what the data showed. And that he should be reassured that the studies supporting the safety of vaccines were well performed and irrefutable. I offered to send him the studies. But Harkin wasn’t convinced. He continued to hold my hand in his firm grip. “Can you tell me with confidence that vaccines aren’t causing permanent damage to children’s brains?” he asked. “Yes,” I said. “I can.” He continued to stare at me, sizing me up. Was I someone he could trust?
In the end, Senator Harkin never asked Congress for that $2 million. I was glad that a lot of money wouldn’t be spent testing something that had already been tested. But in some ways, I felt like we had probably prevailed for the wrong reasons. For Senator Harkin, it seemed as if the issue wasn’t determining the relative quality of scientific studies as much as finding scientists who appeared to be trustworthy. Although scientists say that it’s always about the data, the fact remains that most people don’t have the background to sort out good studies from bad. So they make decisions based on the believability of whoever is doing the talking. This means that charismatic scientists with poor data may be more convincing than awkward scientists with quality data. Appearances win out.
We are, all of us, at the mercy of fringe scientists with winning personalities.