Making a mistake on a science exam is bad. So is publishing a paper with flawed reasoning. But what about being fallible in the first place? That, says David Deutsch, should be embraced.
Deutsch is a Fellow of the Royal Society, a pioneer in quantum computing, and a popular science book author. He is also a dyed-in-the-wool optimist. Why does he think the future looks so bright? Because of our ability to think rationally, and to be wrong. After all, he says, “error is unavoidable in the growth of knowledge.”
He sat down with us to explain his thinking.
What has science proven?
Science never proves anything. Science is full of examples where things that were thought to have been established forever were later found out to be just false. What always happens, though, is that when you find that a supposedly incontrovertible theory was actually false all along, you find that what is true is an even more amazing theory. So when Newton was found to be wrong and [his theories] were superseded by the general theory of relativity, we didn’t go back to Kepler’s theory or the geocentric theory. We went to something that was more amazing than Newton’s theory.
What makes progress possible is not whether one is right or wrong, but how one deals with ideas. And it doesn’t matter how wrong one is. Because there’s unlimited progress possible, it must mean that our state of knowledge at any one time hasn’t even scratched the surface yet. [As the philosopher Karl Popper said], “We’re all alike in our infinite ignorance.”
Why is it good to be wrong?
Fallibilism is the philosophical position that all human endeavors—attempts to create knowledge or achieve anything—are subject to error; that there’s no such thing as a guarantee that a project to create something new will succeed. On the other hand, fallibilism also says that the very idea that we are subject to error implies that there is such a thing as being right—that there is such a thing as the truth and that we can sometimes find some of this truth. So fallibilism, as I understand it, is a fundamentally optimistic, positive worldview. If you look at its negation—which is that there are some things and people that are infallible—that’s all a very pessimistic and frightening kind of take to have on the world.
Why is it dangerous to claim absolute truth?
I should say that this idea that we can obtain certain truth, justified truth, authoritative truth and so on, is very old and has permeated both philosophy and popular culture and everything for thousands of years. If you just think back to all the different claims of infallibility that have been made in the past, including within science, you’ll see that all of them were built on sand. Not only were they factually wrong, they also caused tyranny—either intellectual tyranny or actual political tyranny. Karl Popper said on one occasion “The doctrine that the truth is manifest is the root of all tyranny,” which, when I first read it, sounded rather like an exaggerated claim. But I’ve come to think that it’s true.
What does popular science get wrong?
I think the popular science field creates certain misconceptions about what science is. One is that it confuses people about the difference between the content of a theory and the various metaphors and means of explaining it that have proved to be useful. What happens is that people who aren’t in the field tend to think that the theory is the metaphors.
Another thing that [popular science] has gotten wrong is the idea of a genius or a flash of inspiration. The flash of inspiration implies that science is drudgery except for the occasional kind of orgasmic moment when you know something that no one else knows, whereas in fact science is absolute fun all the way through. And the genius mistake—that’s a really bad one because it makes every reader think that they are not that person. And that is the absolute opposite of the truth. The difference between making progress and not making progress is precisely, and nothing other than, adopting the methods of reason.
The full interview can be seen here.