Irreducible Complexity with Ard Louis

Irreducible Complexity
Conversation with: Ard Louis

Physicist Ard Louis offers his take on the theory of “irreducible complexity” -- the idea that certain complex structures could not possibly emerge via evolution.


To join the conversation about this video, see our post "Reducing Irreducible Complexity, Part III".

Video Transcription

I think the intelligent design argument for irreducible complexity, is basically saying, "Here's a very complex object, like the ones I'm telling you that self-assemble." The argument is this could not have possibly have happened through an evolutionary pathway. I don't think that is the right way of looking at these problems, even for those things where we don't yet know by which pathway these things have evolved. I think that's the wrong way of thinking about it.

The reason I say that is because if I look at something like the bacterial flagella motor, one question is how is it evolved. Another question is how does it self-assemble. In fact, scientists have looked at this question of how things self-assemble for the last few decades. If you just count the number of ways that proteins come together, that are happening right now in your body, thousands of times coming together in little flagella motors, the number of ways they can come together which is wrong is millions and billions and hugely more than the number of ways they can come together that's right.

The system doesn't have time to search through that whole big zoo of possibilities and find that one state which is the correct state for the bacterial flagella motor. But in spite of that, it works. If we didn't see it, we wouldn't believe it. The theoretical arguments that it couldn't possibly come together in the 20 minutes that it takes because it couldn't search through all the possibilities that are wrong to find that one possibility that's right seems very strong. But in fact, we observe that it's true.

People like myself and other scientists have thought about this in a mathematical sense. We now understand why, from the many ways that in can come together wrong, it comes together right, even though there's no guiding hand pushing it. That's something that happens in real time again and again. The fact that it took us a quite awhile to understand these principles makes me think that we could do the same over evolutionary time, over a much longer period of time. There's no reason why, if we think about this long enough, we may not find the answer.

That is perhaps a complicated way of explaining that self-assembly, in real time, would, in fact, if you thought about it in the intelligent design way, use the arguments. In real time it shouldn't come together, but it does. We now understand that it does. But if those things came to use fully-formed, and we didn't see a self-assembly process, you could make an intelligent design type argument to say it could never possibly happen. It's only the fact that we see it that pushes that direction.