(3/2022) The COVID-19 pandemic has given many of us a lesson in how science works. And to be honest, it is not always pretty. The apparent flip-flops in advice from "experts" in science plus the changing interpretations of what is happening and what to do have perplexed many people. The confusion has led some to think that "science" is not so trustworthy after all.
To scientists, by contrast, all those changes reflect a situation that is quite familiar in the early stages of research into any new phenomenon.
Still, it looks bad to a public unfamiliar with the ways of the scientific community, especially when they hear authority figures telling us to "trust the science." That glib slogan assumes that science is one monolithic, infallible, and unchanging thing. It’s not, and the slogan is na've.
The truth is that many people are conflating two rather different kinds of science. "Two" is an oversimplification, but bear with me. There is textbook science and there is what I’ll call cutting-edge science.
Textbook science is what many of us were fed in school—lots of facts and names. Photosynthesis. Proton. Darwin. Stratosphere. Covalent. And dozens more. That’s knowledge that came from science, and it’s well supported by powerful evidence. What scientists actually do, however, is engage in an often-fumbling process of trying to understand how the world works in greater detail than is in the textbooks. That’s where the cutting edge is—in that fumbling process.
Science textbooks are great (and worthy of trust), but they sit on the shelf while the scientist spends days at the laboratory bench trying to make a balky experiment yield results that make sense. Or she pores over spreadsheets of numbers that don’t fit the expected pattern. Or he tries to design a better experiment. Or in fields of science where experiments are rarely possible, as in astronomy or in public health, the researcher plans more extensive observations, perhaps using a newly invented instrument, or looks for some other source of evidence that might answer the question. In all cases, of course, progress must be made within a limited budget.
The cutting edge always slices into the unknown, into darkness. It is not always clear at first what that cut has exposed. In fact, you can often tell that a report of a finding is based on good science if the report states clearly that it is uncertain. An honest scientist who has found something new that seems important will almost always say it is "probably" true. A pretender will claim certainty.
There are very few new findings in cutting-edge science that can be stated honestly with absolute certainty. The closest that researchers usually get is to express a high degree of confidence that something is true. In many cases, there are ways of calculating the degree of certainty in numbers. This may be most familiar to nonscientists when public opinion pollsters state their margin of error. But scientists usually can reach a high level of confidence only after rigorously testing their hypothesis. Or if experiments are not possible, confidence comes only after repeated observations point to the same conclusion.
When cutting-edge science reaches a high degree of confidence in a finding—ideally when several different researchers have come to the same conclusion—the finding goes into the textbook, and the scientists move on, cutting deeper into the unknown, raising new uncertainties.
So it has been with the COVID pandemic.
Early on Tony Fauci, a pillar of science on infectious diseases, says people don’t need to wear masks. Then he "flip-flops" and urges masks.
The FDA gives Emergency Use Authorization to hydroxychloroquine and later revokes it.
Science says the vaccine protects you. Later science says there are breakthrough infections, and you need to wear a mask anyway.
Science says two shots of the vaccine does the trick. Later science says you need a third jab.
Every one of these apparent reversals of what "science says" is explainable by the simple fact that the early pronouncements were based on very little information. We were at the cutting edge of the COVID phenomenon, and as time went on, more data corrected the earlier statements. If you go back and look at what Fauci and other real scientists said, you will find phrasing intended to express a level of uncertainty.
The reversal on mask wearing was different; scientists feared that so many people would buy masks that there wouldn’t be enough for medical workers. The facts changed, and so did the advice. Big time.
Even serious science published in peer-reviewed journals can be wrong. One of the (dirty?) little secrets of science is that that most peer-reviewed and published scientific findings are wrong or, at best, so uncertain as not to be convincing. That’s not libeling anything; it’s simply recognizing that the cutting edge always slices into the unknown.
It's also important to remember that scientists use many different methods that yield many different sorts of evidence, some of which are closer to the truth than others. Medical researchers, for example, speak of "levels of evidence" ranging from reports of individual cases (weakest level) to observational studies (moderately persuasive) to interventional studies such as the "gold standard" of randomized, double-blind, placebo-controlled clinical trials (very convincing, if properly done).
The observational method is what was used to find out how well the vaccines work. You vaccinate a lot of people and simply wait and see how many of them get infected. Then you compare that with the infection rate of a comparable number of unvaccinated people. That is what took so much time.
An interventional study would have vaccinated some number of people and then deliberately tried to infect them with doses of the COVID virus. That would have given an answer much sooner, but the method is considered unethical.
The bottom line in all this is that science is perhaps the greatest invention of civilization but that those of us who are not scientists need to be aware of how it works. We should trust the method—not to achieve certainty right off the bat but to get us as close to the truth as is humanly possible at the moment.
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