309 | Christof Koch on Consciousness and Integrated Information

Hello, everyone. Welcome to the Mindscape podcast. I'm your host, Sean Carroll. Despite multiple episodes here on Mindscape devoted to the topic, we have still not figured exactly out what consciousness is or how it works. We've had philosophers on talking about what it means to have an experience. We've had neuroscientists talking about what happens in the brain, all to no avail. It's not that there's not been progress. I'm I'm slightly tongue in cheek here, but this is a hard problem. What exactly is consciousness? Because it's one of those things we're very, very familiar with, but it's kind of unique in that we're most familiar with it from the inside. Right? Rather than at an objective stance measuring things with calipers or microscopes or whatever, we are experiencing it all the time. That's an opportunity, but it also creates certain unique problems. So today, we're talking to someone who is a neuroscientist, but is also very, very willing to mix it up with the big philosophical questions. Christophe Koch is currently at the Allen Institute for Brain Science, where he was originally the chief scientist and president of the institute. Before that, he was a professor at Caltech for quite a while. In fact, I met Christophe when, believe it or not, we were both consulting on a movie. And the idea of consciousness came up, and the idea of consciousness in a computer came up, and Christophe pulls out his iPhone and points to it and says, how do you know this isn't conscious? At the time, I did not take that seriously, but now I understand that the issue is a lot better and I know that he was gesturing toward the idea of panpsychism, which we've talked about before, of course, on the podcast. And Christophe is not quite a panpsychist, but he's panpsychist adjacent as a a proponent of the IIT or integrated information theory approach to consciousness. It's a very down to earth theory in the sense that there are numbers and equations, and you try to measure the connectivity and the integration of the information in some system. The system might be a human brain, or it might be an AI system, or it might be a pile of rocks on the beach. You can measure its integrated information. But the point is you always get some number, and Christophe's point was, well, that number is not gonna be zero for most systems. It might be very, very tiny, nothing like what we consider to be consciousness, but maybe you can talk about it as a wee tiny bit of consciousness without actually saying that electrons have feelings. So this is years later, and a lot has happened. And we're gonna talk about a number of things that Christophe has done. He's been very involved in figuring out, ever since his early work with Francis Crick, what are called the neural correlates of consciousness. So forgetting about what consciousness is, what …