Curt Defends Sean Carroll to George Ellis

Added: 2026-05-06

[00:00:00]Wouldn't someone like Ashan Carroll say professor Ellis the Python example over here which communicates to assembly code which communicates to machine code when we're saying that something happens at the Python level and it doesn't or that has influence over the electron level.

[00:00:17]We're actually using a shorthand we're calling it Python but it's code code in a different sense it's code for electrons are doing so and so with semiconductors. Yeah.

[00:00:27]>> So if you actually look at what we mean, if someone was to say, well, what do you mean by thermostat? What do you mean by this and that causes so and so? We'll get down to some physical instantiation and it's just physics in the end. That's the reductionist claim. All these you made a decision to do so and so is because of your neurons, because of blah blah blah blah blah.

[00:00:50]>> Well, if you say it's only physics, that's obviously false. If I tell you Maxwell's equations, okay, here's Maxwell's equations. So what does that do? Doesn't do anything. I give you Newton's laws of motion. Tell me what Newton's laws of motion will cause.

[00:01:02]Doesn't do anything. It only does something in a context. And the context is what decides what will happen.

[00:01:08]Physics by itself simply does not decide what happen. Physics enables it to happen. But it it it causes it to happen in the sense that it is told what to do, but the physics doesn't decide the outcome. The context decides the outcome. And um now the thermostat is an extremely interesting example because a thermostat is a very simple system where you can see very clearly what happens and it it's a it's a typical feedback system. You've got a a sensor which determines the temperature. You've got a a a goal which you set on the thermostat. You would like the temperature to be 40° and it's actually 20. you determine the difference and then that difference sends sends a current round to a heater.

[00:01:57]The heater heats it up and that makes it up. So, so this is a classic example of feedback. Um, determine what it is, find the difference and take corrective action to make it correct. Now, this is a case of top- down action because this is all at the macroscopic scale. At the microscopic scale, what happens is that by turning at the macro scale the dial on the thermostat at the micro scale, you cause molecules to move fast. So that's that's top down action. The physics isn't determining what those temperatures should be. It's you are determining it by setting it in on on the dial. And so it's a classic case of top down action. The physics is enabling it to happen. We are we are telling the physics what to do and the physics does what we tell it to do. The physics isn't deciding anything. The physics is the servant, not the master.

[00:02:48]Hi everyone. Hope you're enjoying today's episode. If you're hungry for deeper dives into physics, AI, consciousness, philosophy, along with my personal reflections, you'll find it all on my Substack. Subscribers get first access to new episodes, new posts, as well behind-the-scenes insights, and the chance to be a part of a thriving community of like-minded pilgrimmers. By joining, you'll directly be supporting my work and helping keep these conversations at the cutting edge. So, click the link on screen here, hit subscribe, and let's keep pushing the boundaries of knowledge together. Thank you and enjoy the show. Just so you know, if you're listening, it's cur ji mu n g- a l.org. Kurtjongle.org.

[00:03:31]I imagine a Sean Carroll, if I was to channel Sean Carroll here, would say something like, firstly, your physical system. Now, of course, you can disagree with that, but all of what was just said would just still be accounted for by the microphysics entailing the macro physics. So, that's I imagine what Sean Carroll would say. I think he has an argument about that. I think you have arguments with him as well, but please, I'd like to hear.

[00:03:57]>> The problem is very simple. Sean Carroll doesn't admit the downward causation takes place. That's simply wrong. As a matter of fact, um, dominant causation does take place and there's a variety of ways it takes place. It takes place by setting constraints on lower level variables. Um, and uh, which many people have written about.

[00:04:21]And so a physical law would be of the form a function of uh a constraint is an equation of the form a function of x equals a constant. And you change the constant you change the constraint. Um and now the very simplest one is is a pendulum. And the pendulum you've got a bob which swings and the the the length of the bob determines on what orbit it is. and and you can move it up and down and you can get different rates of swinging. So that's that's a very simple constraint. The constraint is a macrolevel thing. It determines what those microlevel uh particles that make up the bulb do. And of course it's physics, but physics by itself enables it. But it's it's it's it's a technology that the physics is incorporated in which decides what happens. Um and now the human brain is a very very large hierarchical system and it's it's a basic principle. every very very complex system is modular, hierarchical, structure. All of those words are important and um the clearest way you can see this is by talking to computer scientists because computer scientists are the people who've actually built really really complex systems and um and they they use those principles all of the time. So what the the basic principle is you've got a complex thing you want to do and it's very very complex. So you break it up into simpler things and those are still very complex.

[00:06:00]So you break those into even simpler things and you break them down until you have a very very simple thing that can be done in a very simple way because it's now linear. And so then you you then build those back up until you get the thing that you want to happen at the top. And so modular hierarchical structures, every every living thing is a modular hierarchical structure. every technological system, an aircraft, a motor car, the internet, they're all modular. Computer, they're all modular hierarchical structures and every biological thing is a modular. So the basic principle for constructing complexity is modular hierarchical structures that are adaptive and um downward causation takes place in a couple of ways. One is by a can setting constraints and uh another another simple example is just an electric circuit with a battery and a and a light bulb and a switch and you open the switch you close the switch and it allows the current to flow or it doesn't and when the current flows and electrons flow and so on you are controlling what happens at the low level. That's absolutely clearly top- down causation.

[00:07:13]No question about it. Now the other way that top down causation takes place is very interesting. Higher levels you you've got the higher levels made up of out of lower level entities. And what higher levels do in any complicated system is they create modify or destroy lower level elements.

[00:07:34]And that's the core of a huge amount of biology. um gene regulatory networks are there to create uh uh proteins. So so the the system as a whole a gene regulatory network is a very complicated thing which reacts to high level conditions and it is built in such a way that it will generate proteins. Um so mod modifying them takes place all the time and the classic example of that is is developmental biology in which you have a set of cells and they're all basically the same to start with and then in the fruitfly for example at different places signals get sent positional signals which tell different genetic circuits to turn on and off at different places and that creates all of the the body plan of of of of a fly, a mouse and a human being. It's where we get our backbone from. And so um that that is and what happens there is cells are changing their structure. It's cell which starts off cells start off pur potent. They can become anything. But these processes turn cells into specific things into blood cells, neurons and and so on and so on. And so things are created, they're modified, and they are destroyed. And epoptosis is programmed cell death. And for instance, when we're when our hands are developing, initially they're all joined together. And then the cells between are destroyed and that enables us our fingers to be separate from each other. And so these are three different kinds of things that take place. And they take place in physics as well. and and in organizations these principles are extremely general and there's an organizational analogy for all of them and the organization one is a very interest one an organization let's say the Boeing aircraft company it's a huge modular hierarchical structures very very large and um what happens is uh t take for example the employees there's a process for for letting employees join the company and you select who's going to join That's a process of bringing in. Once they're members of the company, you train them.

[00:09:55]You train them into a specific task. And that means you're modifying them. By the time you've trained them, they're not the same as they were before you started training them. And then there's a process of assessment. And either they make the grade, in which case you keep them, or they don't, in which case you you boot them out. And so the this this process of higher level selecting what happens at lower levels, it happens in technology, it happens in biology, it happens in um in organizations. As I say, these are very very general principles which apply across the board in truly complex systems. And there's not the slightest question that downward causation is taking place in any of these cases.