On April 6th of this year, WHO recommended that healthy people not wear masks. On June 5th, they recommended that everyone wear masks if transmission of the coronavirus is widespread. Recently, Anders Tegnel, the chief epidemiologist in Sweden downplayed the importance of masks (although he admits that they can help). On this issue of great import, science seems to say one thing, then another.
So can we trust science?
Some Say “no”
Some have seen medical science’s reversals as evidence that science does not work—that we cannot trust it. The mask discussion above only illustrates a common place reality that science often claims one thing and then later revises its position.
Given the revisionary conclusions of science, many have simply lost faith in it. Small wonder then that large numbers of North Americans carry skepticism about vaccines, 5G, and other medical and technological advances.
So, then, I have to ask again: can we trust science?
Why We Can Say “Yes”
We can trust science but only if we know what science is. Most of assume science provides certainty about the world around us. It does not. It is not meant to. And by its very nature, science can only provide probable answers to our questions—never certain ones. At least, if certainty means an answer that can never be improved upon or revised.
Theoretical physicist Carlo Rovelli describes science as being reliable because “it provides us with the best answers we have at present” (2017: 260). “Science is not reliable,” he writes, “because it provides certainty.” (260).
New findings bring improvements and revisions to science. And so scientific answers are not definitive. “They are reliable because they are not definitive” (261), explains Rovelli. Good science involves “a radical distrust in certainty” (261).
And this must be the case since science observes the natural world, forms hypotheses, and tests them. It discovers little by little glimpses of the nature of things. But the vast mystery of the universe from biology to quantum mechanics still eludes our full understanding. We are small; the universe is not.
Certain and Probable Knowledge
The limits and prospects of science should not surprise us. The merely probable nature of natural science is just what it is. It cannot be more than it is. We should not expect it to provide absolute certainty—if that means its conclusions can never be improved upon or challenged.
Yet this probabilistic nature of natural sciences does not make it useless. We live on probability. I have sat on chairs many times. I predict the next time I sit on a chair it will not break. I am usually right. So, my science here proves rightly almost all the time. It works. That’s just life.
(It is a bit more complicated than I make it sound because some truths can form first principles for sound conclusions. And some metaphysical conclusions can have certainty. But let’s forgive my oversimplification for the sake of argument).
Thomas Aquinas (1225–1274) helps us think through certain and probable knowledge—at least when it comes to faith. He distinguishes certain beliefs of Revelation (scripture) and probable conclusions that come from authorities (philosophy, theology). In his first question of the Summa, he explains:
Nevertheless, sacred doctrine makes use of these authorities as extrinsic and probable arguments; but properly uses the authority of the canonical Scriptures as an incontrovertible proof, and the authority of the doctors of the Church as one that may properly be used, yet merely as probable. For our faith rests upon the revelation made to the apostles and prophets who wrote the canonical books, and not on the revelations (if any such there are) made to other doctors. (I.Q1.A8).
Thomas tells us that Scripture informs our faith certainly. External authorities can only give probability.
I think by analogy we can think about how science works. Science may have certain first principles (reason, etc.). But it can only provide probability.
We can trust science because it is open to revise and modify its conclusions. It admits wrongs. It corrects them. We cannot trust science to provide certainty about ultimate things. That alone belongs to revelation.
We trust doctors. We should. We trust our senses. We should. We trust many kinds of experts. We should trust them all—as long as we can verify they have the expertise that deserves trust. But we give anyone the kind of trust they deserve: merely probable.
Yet that does not mean chaos and complete uncertainty. I always sit down on my chair expecting it not to break. That’s the only way I can live. Probability is not bad; it just has limits. So then does science. And that’s okay.
This article originally appeared here.