December 18, 2019
What is your reaction to the reputation of science these days, particularly at the highest levels of our government?
Science is in some ways its own worst enemy in that regard because what’s happened is that there are things that science has done a really good job of establishing. There are things where there is science that can be said about them, but it’s kind of overreached in some way or another, and people then get suspicious. People would say… for example, evolution. “Evolution is the whole story of biology”, people would say. Well, it’s not. There’s other things going on, and some of them I’ve figured out in the science of how complicated forms arise in biology, which is something where people say, “It must just be evolution because evolution is all there is”.
Actually, evolution on its own can’t explain why there are complicated forms. That’s a computational phenomenon that is similar to this rule 30 phenomenon, where the rules can be simple, and the forms that are produced aren’t simple. It’s a place where when people just say, “It’s evolution, that’s all there is. If you say there’s anything else to biology other than evolution, you’re wrong”. That’s an overreach in the sense that actually there is something else going on, which is nontrivial science. It’s not that the other thing that’s going on is not science. It’s absolutely science. It’s probably cleaner science than evolution, in many ways. But it’s something where people say, “We’ve got one piece of science, let’s carry that all the way”.
I think the other thing that happens… there’s an important phenomenon not yet well understood, although I happened to testify for a Senate subcommittee a couple of months ago and now this term is in the congressional record. I don’t know what that means about it. The term is computational irreducibility. What does that mean? You say, “I know the rules for how some system behaves. I can figure out everything about what the system does”. Actually, that’s not really true, because you might run the system for a billion steps and you have to go through all those billion steps. The question is can you figure out what’s going to happen in the system more efficiently than just running those billion steps? You’d have to run all those steps and see what happens.
That’s important when it comes to predicting the climate or something. The question is, can you just say, “This is the answer”, or is this a computational irreducibility phenomenon that means there’s an irreducible amount of computational work you have to do to figure out what’s going to happen, and where it’s very hard to make simple “Oh, it’s just going to do this” claims. One of the things that happens is people will say, “We have this science. We know something about this scientifically. We will take that particular idea in science and take it to its end conclusion. Because it’s science, that must be the whole story”. But actually, it’s not. You’ve just got one particular piece of the science, and you forgot about other parts, particularly this phenomenon of computational irreducibility that means even though you know the equations for things about fluid in the atmosphere and so on… even though you know that, doesn’t mean it’s easy to tell what’s going to happen.
I think what has tended to happen is that people have said, “Science is the new religion in many ways”, in the sense that people say, “We believe in science”. In some ways, they believe in a version of science that isn’t well informed by things like computational irreducibility. They believe in a version of science that has simple cut-and-dried answers to things. Other people say, “Common sense tells me this can’t be right”, and they’re right. It’s not right. It’s a piece of the story, and there are certainly places where that story comes through for science spectacularly. But there are other ones… including some of these most controversial ones, whether it’s in a medical area or in climate… where it’s not so obvious. It’s not something where it’s a cut-and-dried story.
Now, people can come up with crazy conclusions. I’m not arguing that all the things that are said that are on the other side from the cut-and-dried science make sense, but it isn’t true that the cut-and-dried science is really the whole story. I feel that actually it’s a thing where science has done itself a considerable disservice by trying to make things seem cut and dried and simple when they’re actually not. Some people are rightly suspicious and say, “It can’t be the whole story”. Then there’s an attack on science as a whole, which is also unfair.
I think it’s a more complicated picture. I always kind of wince when I hear “Science has proved that blank blank blank”, when it’s like, “I know how the science works. You can’t possibly have proved that”. It’s a much more complicated story. There are things you can say, but there are also a lot of footnotes and caveats and so on.