The Evolution of Consciousness | Dennis Noble

Added: 2026-05-19

[00:00:00]That is the question of uh mentality, uh cognition, particularly consciousness, uh is usually in philosophy of mind, neuroscience, in that area. Um what can be said from an evolutionary point of view as to the development of these characteristics? And many people have many ideas, of course. Uh but I'd like you to reflect upon it from your very original way of of thinking uh through systems biology and top-down causation and recurrent causation.

[00:00:33]Well, I'm a physiologist.

[00:00:37]I know that our nervous systems, brain in particular, but the rest of the system, too, consumes a huge amount of energy. Yeah, 20% of the body, I think, yeah.

[00:00:49]>> Huge.

[00:00:51]Now, what evolutionary process would allow that to happen if there wasn't a really major advantage?

[00:01:01]And the advantages are obvious. We can anticipate the behavior of predators.

[00:01:08]And if we are predators ourselves, we can anticipate the behavior of prey.

[00:01:14]We are thinking.

[00:01:17]There's no question about it. So, organisms have to have that anticipatory process.

[00:01:24]Now, you can call that mind.

[00:01:27]You can call it consciousness. I don't mind what you want to call it. I literally don't mind.

[00:01:34]In the sense that it seems to me these are processes that bring into our bodily processes the interaction between our social relationships, our values, if you want to call them that, and the way we align our bodily processes to fit with all of our social interactions. That seems to me to be not a bad way of saying what the mind is.

[00:02:03]So, let's tease apart two things that I think you said. One is what was the motivation or the driving factor to create this? And that's the anticipation or the predictive ability of the organism, whether it's in a bacteria or amoeba Yes.

[00:02:22]So, prey situation that you talked about. So, that's the the driver of it.

[00:02:27]The second question is, what is the mechanism of it? Now that we know it's selected for, but we don't know what that says almost nothing about how it works internally. It's you know, how that mentality actually functions. I think the nervous system can take a leaf out of the system called the immune system. And I'm not the first person to suggest that. Gerald Edelman, many years ago, who won the Nobel Prize for understanding the nature of the molecules >> went the other direction. He went from the immune system to neuroscience.

[00:03:03]>> Precisely, and he produced the idea of neural Darwinism, he called it. Now, the reason I say that is that I think that what nervous systems are extremely good at doing is producing a vast number of anticipatory scenarios.

[00:03:21]And that is the process we're so good at as humans, but I think the big apes certainly do it. I think my cat does it.

[00:03:30]I think that even probably a bacterium does it to some degree.

[00:03:34]And we're talking about degrees here.

[00:03:37]Now, there has been recently, by people working in evolutionary biology, but in a physiological context, an attempt to understand what is the breakthrough that enables that to become what we now call consciousness.

[00:03:53]And what I think is the breakthrough is going from the ability to have uh limited variability in what we can do to the ability to have almost unlimited possibility of associations.

[00:04:12]Our language illustrates that beautifully, and that's depends upon our nervous systems operating the way they the way they do. And what's happening there is we and birds and whales and any user of language can actually string together endless dialects and ideas.

[00:04:30]It's as it were jumping out from being just the physical body one is to the world of ideas. That's what gives us the ability to have insight. That's what gives us the ability to anticipate successfully. So, it multiplies the possibilities of the things that we can work with. Uh for the selection process.

[00:04:52]Absolutely so. In in the whole process of of selection, the first thing that you need is to have the universe of of options with which you work.

[00:05:02]>> Indeed so. And what you're saying is that the the nervous system then supplies vast numbers.

[00:05:08]>> Indeed so. And if you study the organisms we have today and ask which of those that are capable of doing this unlimited associative learning as we can call it, the possibility of that almost endless combinations as our language is show, but not just our languages.

[00:05:27]If you ask the question, how many of those organisms existed at the time of the Cambrian explosion?

[00:05:33]Almost none.

[00:05:35]>> Mhm.

[00:05:36]Why was it an explosion?

[00:05:38]Why did it suddenly radiate out over just a few million years? I know it's a long time in one sense, but in an scale, it's actually very rapid indeed.

[00:05:49]And that's what we see in the geological record. You find it exploded.

[00:05:54]I think it is the ability to have unlimited ability to anticipate the activity of other organisms. Now, I'm not the person who developed this particular theory that the Cambrian may be the point at which it happened. That is the thesis of Ginsburg and Jablonka wrote a very important book called The Evolution of the Sensitive Soul. And soul here is not used in a religious sense. It's used to refer to this ability to have unlimited association. In other words, to be conscious of everything that's happening around us and to be able to integrate that into anticipatory action. That's my definition of consciousness.

[00:06:37]I'm happy for somebody else to come up with another definition.

[00:06:39]>> [laughter]