Matthew Cobb is a zoologist. Like many other scientists, he tries to tackle seemingly insurmountable problems by breaking them into parts, and looking for more accessible comparisons. For example, the 66-year-old professor from the University of Manchester is studying the sense of smell of worms that have 21 cells in their nose, to try to understand what happens in ours, which has four million cells.
A few days ago, he gave a lecture at the Autonomous University of Madrid titled The Idea of the Brain — which is also the name of a book he wrote in 2021. In the book, Cobb talks about the history of neuroscience, the advances of the last few decades and why it is we know so little about the organ where our consciousness resides. The professor, who has also published a book on the race to crack the genetic code, points to that challenge as an example of human’s ability to successfully tackle great enigmas by asking the right questions and developing the necessary technologies.
Question. In your book, you talk about how scientists use metaphors to make problems more understandable or as a form of inspiration. Are there metaphors about the brain that have become exhausted or that stand in the way of progress?
Answer. We first thought that computers should be like brains. Now, the metaphor we currently have is that the brain is some kind of computer, which is true to an extent. We understand the calculations that are going on in your phone right now. We understand that they have been designed. But there are very few calculations or computations at a cellular level that can actually explain what the animal is, or why it’s deciding to turn left or right or move towards the light. The computer metaphor is valuable. It helps us understand the kinds of things that might be happening in a brain, but we’re perhaps getting to the edge of that usefulness. We need to think about what the brain is doing in more organic, ways and not in cynic silicon digital ways.
Brains are not digital, nervous systems are not digital, they are primarily analog. They’re not like any machine we’ve ever built. When you’re tired, you don’t function so well. Your computer’s always the same, as long as it’s got battery. We have hormones that change how our nervous system functions. Machines aren’t like that. We’re getting to the point the computer metaphor is very useful for explaining [the brain] to the public, but as a source of inspiration for scientists, I’m not sure it really helps anymore.
Q. Are we getting at least a little closer to understanding the brain?
A. There is an American researcher named Eve Marder, and she has spent her whole career understanding, studying the lobster, but not the lobster’s brain, its stomach. The lobster has a stomach with muscles that grind up its food. And it’s got 30 neurons in that stomach which control these contractions. She knows everything about those neurons. And yet she can’t explain why those 30 neurons only produce those two rhythms and why there are other neuronal organizations to produce those two rhythms. She can’t explain what will happen. She can’t predict using computer models.
At the end of the 19th century, a great wave of doubt spread over all of science. People began to think that we would never understand things. This gave rise to vitalism, the idea that there were vital forces to explain the phenomenon of life. The response of scientists beginning in the 1920s was to try to reduce the problems to more fundamental explanations. And so they saw that genes were not forces. Initially, they thought they were made of protein, and then they were able to show that they were made of DNA. And finally, they were able to understand the structure of DNA and see in principle how a gene could encode a protein. That was achieved by trying to reduce the problem to its simplest aspect. My feeling is that the kind of work that Eve Marder is doing will allow us to move in that direction.
Q. Do we have any ideas about when consciousness arises in the evolutionary process, whether it exists in animals and whether or not their consciousness resembles ours?
A. Darwin was very interested in this problem and found a very easy solution. The shape of the brain determines your behavior, and we can call it consciousness. There’s a link between matter and thinking. And what Darwin said is, ‘Well, if that’s true, then natural selection, which gives us hands, which gives a giraffe a long neck, will also change the shape of your brain and, with it, your behavior.’ It can explain why different animals behave in different ways.
Although he didn’t want to, Darwin also wrote about human evolution and published The Descent of Man. He had to publish it because his great colleague Alfred Russell Wallace, who became very interested in spiritualism, argued that humans were different, that we weren’t subject to the same laws, and Darwin was convinced we were. In the book, there is a comparison of the brain structure of all the primates. And what Darwin says is if you just look at structure, there’s no difference of kind, there’s simply a difference of degree. The structure is basically the same, with slight differences in organization, for example, in gorillas; but from the outside it looks very, very similar. So you can see how this very slow evolution has produced different brain shapes and different behavior. Now, clearly there are some things that I can do that a gorilla can’t, like talk to you.
There is a similarity between us and apes, but we have different ecologies. Humans are incredibly co-operative. We have terrible wars. We can kill people, but we are amazingly cooperative. We are kind, generous, and we have collective child-rearing, although we don’t now. In anthropological terms, child-rearing is shared in a way that isn’t the case in any of our great ape ancestors. We are also genetically very closely related. We know from genetics that the human population about 70,000 years ago was about 10,000 people. Something bad happened to Africa, and we see that restriction of genetic variation. So we are very similar and cooperation is inscribed in our society. Think of chimp confrontations. It’s all about violence and intimidation, which clearly exists in human societies as well. But it’s not the essence of it. The essence is our collaboration.
If you look at chimpanzee confrontations, they are terrible, and they have levels of intimidation and violence that, although they exist in human societies, are not in their essence, and it is what has given us our power. Think for a minute of octopuses. Octopuses are very, very smart. They can perform amazing tasks, they can remember stuff. But who’s in charge? It’s not the octopus. We’re in charge. An octopus is a solitary creature. They only meet to mate. They don’t have any collaborative work at all. Whereas for humans, that’s always been the essence of our survival. We couldn’t have left Africa and gone up to the Arctic without collaborating. No other animal has been able to do that. That is our intelligence. But our intelligence has been driven by our ecology.
So are other animals conscious? Well, I don’t know that you are. I can’t prove that. We assume that other people are conscious. We have to, otherwise life wouldn’t work. And if you then look at a gorilla, it’s very hard not to think that it has the same kind of feelings as we do. Perhaps even cats and dogs. You ask anybody, Is my dog conscious? They’ll say: ¡Yes, of course.’ But I can’t prove that. You can’t prove it with a human.
Q. Do you think it will be possible to turn your mind into a machine to achieve immortality, as some transhumanists propose?
A. This is a very old-fashioned idea. Even if you express it in terms of neural networks and you give it a science vocabulary, what they’re saying is a bit like Descartes and the old idea that you have a brain, and then there’s an interconnection between your brain and this spirit, which is your mind.
The people who think if they’re going to download or upload their consciousness, what they really mean is there’s some state which they can put onto a device. But you have 80 billion neurons in your brain, trillions of synapses and your neurons are not binary. I don’t know how to capture that. Nobody does. It’s not the equivalent of what is on a computer. In a computer, there are chips that respond to the screen or the keyboard, but we know that in the brains of mice, there are structures that will respond to odors. But over a period of weeks, those neurons change. The animal is still responding to an odor, but different neurons are now represented. You have different neurons representing the same state as three weeks ago. Now, this is only known in mice for the moment, but I assume that it will be similar to humans. Whereas your machine is fixed, it’s always doing the same thing.
Q. Could people who are fascinated with the possibilities of ChatGPT, and artificial intelligence in general, be falling into a trap of using our theory of the mind?
A. Absolutely. That happened to that Google engineer who decided that he had spoken to a conscious machine and went to the press. They fired him, quite rightly. He was fooling himself, and you’re the easiest person to fool. Dick Feynman said that the essence of science is you’ve got to be careful of fooling yourself.
With ChatGPT I have been concerned as a teacher. I gave it some of my exam questions that I had asked students. It didn’t produce good answers, but it didn’t produce awful answers. It could probably pass at a university with a mark of 40%. But I thought we can avoid this if we ask more complicated questions. And I have also given essays written by ChatGPT to my students and all said the same thing: it’s a bit rubbish. They could be critical. They understood that the references at the end of the article were all made up. This is a challenge, because it writes plausible things that are false. I’m very concerned about misinformation. But I’m much more concerned about politics. I think in academia we will be okay.
But I’m not worried about these things becoming conscious because that just that’s not what they’re doing. Get me a system that can predict which way a maggot will turn. We can’t understand that. We can’t understand the lobster stomach.
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