“What is it like to be a bat?” famously asked Thomas Nagel in 1974 in The Philosophical Review. It may sound like a silly question, but it has profound implications. We quite literally make sense of the world through our touch, sight, hearing, smell, and taste. Our sense of space in particular is governed in a way that is very different from a bat. Bats use echolocation, a phenomenon we understand very well in theory, but can’t really imagine. What is it like indeed? By asking this question, Nagel asks forces us to make the distinction between subjective and objective concepts, between the outside world and our inside world, between our perception and reality. Asking what it’s like to be a bat is wondering about the nature of consciousness.
It is one of my long-term ambitions to write a much longer essay about what scientists call “the hard problem of consciousness” but for now I would like to explore a tangential concept, which I discovered through Dr Derek Tracy, a senior lecturer at the Institute of Psychiatry, Psychology & Neuroscience of King’s College London.
Consciousness from animals to humans
Three and a half billion years of the evolution of nervous systems, and here we are: human beings, with a human brain. What did it take to get there? How can we differentiate between the complexity of our consciousness and the apparently simpler perception of the world other animals display? According to Dr Derek Tracy, living organisms have various degrees of mentalisation—the ability to understand the mental state of oneself or others.
- First order of mentalisation: I exist. Many organisms are not aware of their own existence. We can assume a bacteria doesn’t have this level of awareness. But take a more complex organism, such as a spider. It doesn’t go much further than this simple awareness, but it knows it exists. It detects vibrations in its web, “decides” whether to attack and eat the prey. (I used quotation marks because this automatic behaviour probably doesn’t involve lots of decision-making as we usually mean it)
- Second order of mentalisation: you exist and are different from me. Take a mouse, a cat, or a dog. They know they exist, but they’re also aware you exist. They can tell the difference between an inert object and another living animal. For some animals within the second order of mentalisation, they will even recognise you over time.
- Third order of mentalisation: I know you know I exist. This is what scientists call Theory of Mind—an ability which is incidentally often disturbed in people with an autism spectrum disorder. While a dog or a cat will recognise you, and know that you exist as a separate living entity, they don’t have the ability to project themselves into your mind. Theory of Mind and the third order of mentalisation are about being able to imagine that another entity will think differently from you. There is lots of controversy around the presence of Theory of Mind in animals, but some scientists think that great apes are able to project themselves in such a way.
- Fourth order of mentalisation: You know I know you know I exist. Yes, this is starting to get quite complex. Dr Derek Tracy uses lyrics from a song by One Direction to illustrate this one: “You know, I know, you know I’ll remember you”—and works backwards. First, “I’ll remember you”, first order of mentalisation. Then, “You know I’ll remember you”, second order. “I know, you know I’ll remember you”, which is the third order of mentalisation—theory of mind. And finally, “You know, I know, you know I’ll remember you”—fourth order of mentalisation. Some scientists think Neanderthal was capable of fourth order of mentalisation, and small children also display this level of mentalisation.
- Fifth order of mentalisation: metacognition. This is where Homo Sapiens is, as far as we know, different from any other animal on Earth. No, we’re not going to add another line to the One Direction song—that would be quite tedious. The fifth level of mentalisation, metacognition, is thinking about thinking. It’s an awareness of thought itself. It’s quite complex and beautiful. Fifth level of mentalisation is when you stop living in the moment. It’s thinking about the past, worrying about the future; asking where your dead has gone, if the world will end, if your children will be fine tomorrow and in many years from now. Metacognition is what gave birth to culture, art, science, philosophy, and religion.
From a neuroscience standpoint, it’s interesting to note that Neanderthal, despite their bigger brain, probably lived much more in the moment. The part of their brain that was much more developed was the occipital cortex, which gave them a much better vision than ours.
A theory is that being from the now European part of the world where the nights were longer, it allowed them to hunt when it was dark, whereas Homo Sapiens from sunny Africa never needed to develop a better night vision.
Our brain is overall smaller, but our prefrontal cortex—the “thinking” part of the brain—is much bigger. As I heard Dr Derek Tracy say during a lecture: “Neanderthal were big in the wrong place.”
Now, a question you may be asking yourself is: why stop at five levels of mentalisation? If it feels arbitrary, it’s because it is. There is absolutely no reason whatsoever for these degrees of mentalisation to stop at the Homo Sapiens levels. There is no reason for our level of consciousness to be the highest level of consciousness.
Beyond human consciousness
It is impossible for a spider to imagine the concept of a dog. It is impossible for a dog to project itself into the mind of a small human infant. It is impossible for a chimpanzee to even grasp some of the concepts we often think about—the meaning of life, the vastness of the cosmos. As Dr Derek Tracy said: “A goldfish doesn’t know it’s in a bowl. A dog cannot know that other organisms can think differently to it.” There is a hard, impassable line between each order of mentalisation.
If we accept the fact that every time there’s a step up, lower orders can’t conceptualise it, then we need to consider the logical conclusion: if an entity with a sixth or higher order of mentalisation was trying to communicate with us, we would not be able to understand it. This is very different from the traditional worry of a language barrier as you see in the (amazing) movie Arrival—this would mean the inherent, unchangeable inability to even become aware a higher order entity is trying to make contact.
To come back to more practical issues, a surprisingly high number of artists and innovators suffer from psychosis. Shine On You Crazy Diamond by Syd Barrett, who was the lead singer of Pink Floyd and developed psychosis, can be interpreted as his experience dealing with what is considered a disorder by modern science. Nobel prize laureate John Nash spent several years at psychiatric hospitals being treated for paranoid schizophrenia.
When you think about your favourite artist, what do you like? We tend to enjoy the work of artists and innovators because they tell us something new about the world. Something we wouldn’t have been able to conceptualise ourselves. Maybe these artists, innovators, and people suffering from psychosis—who tend to overperceive the world—are closer than us to the sixth level of mentalisation.