My intellectual journey to (dis)solve the hard problem of consciousness

Epistemological status: At least a fun journey. I wanted to post this on April Fool’s Day but failed to deliver on time. Although April Fool’s Day would have been lovely just for the meme, this is my best guess after thinking about this problem for seven years.

I invite you to dive deep into the consciousness iceberg with me. The story will be presented chapter by chapter, presenting you with the circulating ideas I’ve absorbed, building ideas in your brain to deconstruct them better until I present you with my current position. Theoretically, this should be easy to follow; this post has already been beta-tested.

We’ll go through a pre-awakening phase, during which I was unfamiliar with the theory of mind literature, then an awakening to the problem of consciousness, followed by a presentation of some essential elements of the scientific literature on consciousness, and finally, a phase of profound confusion before resolving the problem. The chronology has been slightly adapted for pedagogical purposes.

Why do I think this is important? Because I think more and more people will be confused by this notion as AI progresses, I believe it is necessary to be deconfused by it to have a good model for the future. I think one of the main differences in worldview between LeCun and me is that he is deeply confused about notions like what is true “understanding,” what is “situational awareness,” and what is “reasoning,” and this might be a catastrophic error. I think the tools I give in this blog post are the same ones that make me less confused about these other important notions.

Theoretically, at the end of the post, you will no longer ask “Is GPT-4 conscious or not?” by frowning your eyebrows.

Oh, and also, there is a solution to meta-ethics in the addendum.

If you’re already an Eliminativist, you can skip right to Chapter 7, otherwise, well, you’ll have to bear with me for a while.

Chapter 1: Pre-awakening, before stumbling upon the hard problem

Philosophy class: Freud’s consciousness iceberg, I’m going to nail this dissertation.

In high school, I was a good student; in philosophy class, I was just reciting my knowledge to get good grades. We discovered Freud’s framework on the conscious/​preconscious/​unconscious. At the time, I heard people say that consciousness was mysterious, and I repeated that consciousness was mysterious myself. Still, I hadn’t really internalized the difficulty of the problem.

Magic believer: Consciousness is just eMerGeNCe!

As a good scientist, I was trying to understand the world and had the impression that we could understand everything based on the laws of physics. In particular, I thought that consciousness was simply an emergent phenomenon: in other words, atoms form molecules that form organs, including the brain, and the brain gives rise to various behaviors, and that’s what we call consciousness.

Cool, it’s not so mysterious!

In the end, it’s not that complicated, and I told myself that even if we didn’t know all the details of how the brain works, Science would fill in the gaps as we went along.

Unfortunately, I learned that using the word emergent is not a good scientific practice. In particular, the article “The Futility of Emergence” by Yudkowsky convinced me that the word emergence should be avoided most of the time. Using the word emergence doesn’t make it possible to say what is conscious and what is not conscious because, in a certain sense, almost everything is emergent. To say that consciousness is emergent, therefore, doesn’t make it possible to say what is or what is not emergent, and thus isn’t a very good scientific theory. (Charbel2024 now thinks that using the word ‘emergence’ to point toward a fuzzy part of the map that tries to link two different phenomena is perfectly Okay).

So we’ve just seen that I’ve gradually become convinced that consciousness can’t be characterized solely as an emergent phenomenon. I’ve become increasingly aware that consciousness is a fundamental phenomenon. For example, when you hear Descartes saying, “I think therefore I am,” my interpretation of his quote is that consciousness is sort of “the basis of our knowledge,” so it’s extremely important to understand this phenomenon better.

Consciousness is becoming very important to me, and I have a burning desire to understand it better.

Chapter 2: Awakening to the problem

In this chapter, I’ll explain how I gradually became familiar with the literature on the philosophy of mind, which deals with the problem of consciousness.

Consciousness became increasingly important to me, and I started reading extensively. I stumbled upon a thorny mystery: how are the brain’s physiological processes responsible for subjective experiences such as color, pain, and thought? How does the brain produce thoughts from simple arrangements of atoms and molecules?

Memetic awakening: “This is the biggest problem of all time!”

This is the HARD PROBLEM of consciousness, which describes the challenge of understanding why and how subjective mental states emerge from physical processes. Despite numerous advances in neuroscience, this problem remains unsolved.

The Hard problem? Wow, I’m really interested in this. It’s the problem I need to work on, and I’m a bit more delving into philosophical literature.

In philosophy, there are two main types of consciousness:

Access Consciousness:

  • It is the process by which information in our mind is accessible in cognitive operations, such as retrieving information from short-term or long-term memory.

  • It is often considered more easily observable, as we can track the transfer of information from one brain area to another.

Phenomenal Consciousness:

  • Subjective experience is often referred to as qualia.

  • “What it is like to be conscious.”

  • It is considered more challenging to explain and scientifically study because it is inherently subjective.

Here is a “metaphysically and epistemically innocent” definition from Schwitzgebel (2016):

Phenomenal consciousness can be conceptualized innocently enough that its existence should be accepted even by philosophers who wish to avoid dubious epistemic and metaphysical commitments such as dualism, infallibilism, privacy, inexplicability, or intrinsic simplicity. Definition by example allows us this innocence. Positive examples include sensory experiences, imagery experiences, vivid emotions, and dreams. Negative examples include growth hormone release, dispositional knowledge, standing intentions, and sensory reactivity to masked visual displays. Phenomenal consciousness is the most folk psychologically obvious thing or feature that the positive examples possess and that the negative examples lack.

At that time, I did not know that the very existence of the hard problem was debated in philosophy.

Python beginner: Functionalism, let’s go!

When I encountered this hard problem, I was a computer scientist. So, I was trying to imagine how to “code” every phenomenon, particularly consciousness. I wondered what lines of code were needed to code consciousness. I was a functionalist: I thought we could explain everything in terms of functions or structures that could be implemented on a computer. Not for long.

Church-Turing hypothesis: Cite me if you pedantically need to justify functionalism.

Functionalism and the potential to replicate the consciousness or functions of a brain within a computer yield surprising outcomes. Computers and Turing machines are not restricted to a single physical substrate. These Turing machines can be realized via a multitude of different media. Various substrates, such as brain tissue, silicon, or other materials, can implement complex functions.

As an example of a Turing machine, we could imagine people holding hands. So we could imagine simulating the functioning of the brain’s 100 billion neurons by 100 billion people simulating the neurons’ electrical stimulation by holding hands.

This hand-holding system would then be conscious? WTF

The functionalism philosophy seemed to imply things that were too counterintuitive.

There, I discovered the philosopher David Chalmers, who rigorously defended the hard problem.

Chalmers fanboy: This is my man. The hard problem is real. Nice style btw

Chalmer tells us that there is a gap, an explanatory gap, between physical and mental properties.

The explanatory gap in the philosophy of mind, represented by the cross above, is the difficulty that physicalist theories seem to have in explaining how physical properties can give rise to a feeling, such as the perception of color or pain.

For example, I can say: “Pain is the triggering of type C fibers,” which is valid in a physiological sense, but it doesn’t help us understand “what it feels like” to feel pain.

I also met Daniel Dennett.

He impresses me with his ability to discuss many subjects. Unfortunately, even though he’s relevant to many subjects, I had the impression that everything he said about consciousness was either trivial or wrong and that he was dodging the issue of the hard problem.

Dennett & eliminativists: Wow, this man is spot on everything, but everything he says about consciousness is either trivial or wrong; nice beard btw

For him, there are no mental properties to explain.

For him, there are no mental properties to explain. We call this “Eliminativism”: he wants to eliminate the concept of qualia; there is no hard problem. Science can explain consciousness, and he’s a physicalist, i.e., he thinks everything can be explained in terms of physical properties.

Dennett does not convince me. It seemed to me he was just repeating: “What do you mean by qualia?” and he was just plainly ignoring the problem. I was paying attention to what he was saying, but what he was saying was very alien to me.

Obsessed: And I’m still the guy who talks about the hard problem at the party.

It doesn’t satisfy me at all.

The more I think about it, the more I think this is a crucial subject. If AIs were conscious, it would be the craziest thing in history.

Chapter 3: Let’s try the scientific method!

Okay, okay. I will introduce you to three methods: Global Workspace Theory (GWT), integrated information theory (IIT), and the list of criteria method.

But before that, I also thought that becoming an expert in Artificial Intelligence would help me better understand consciousness. Done. Unfortunately, I didn’t learn anything about consciousness.

Global Workspace Theory

Internship in Neurospin

After my Master 2, I interned at Neurospin, a laboratory for studying the brain south of Paris. The lab is led by Stanislas Dehaene, one of the founding fathers of Global Workspace Theory and the author of “Consciousness and the Brain.”

At first, I was pretty unimpressed by Cognitive Science, and I said stuff like, “EEG or fMRI statistics are a dead end, a bit like trying to read the stains in coffee grounds or understanding computers by analyzing the Fourier spectrum of the ventilator noise…”

Until I saw the following experiment:

Masking is an experiment used in the laboratory to make numbers, letters, and objects disappear from consciousness. You stare at the screen, and a number appears, followed by a mask. Then, you try to name the number to identify it.

The number will appear for 300 milliseconds:

You probably don’t have any difficulty to spot the 9.


Ok, now let’s try with 33 milliseconds:

Most of you should no longer be able to see the figure.

It’s even hard to believe that there’s still a number. But I swear to you, there’s still a number;[1] the number appears on your retina but is no longer in your consciousness.

To sum up:

  • if the duration of the number’s appearance is short, the signal is subliminal

  • if the duration of the signal is long, the signal is conscious

Question: where does the signal go? Why does it fade before consciousness?

The Reportability Criterion & The Neuronal Correlates of Consciousness

All these experiments allow us to measure access consciousness in adults using the reportability criterion. The reportability criterion means being able to say, “I saw the number” (other criteria are used in babies and animals).

We can then measure the Neural Correlates of Consciousness, which constitute the smallest set of events and neural structures that activate in a highly correlated way with the subject’s report.

Subliminal vs Conscious processes according to the Global Workspace Theory

What happens is that the visual signal reaches zones V1 and V2 at the back of the brain, and then there are two possibilities:

  • Either the signal is not of sufficient duration, and the signal fades away (left).

  • Or, if the signal is sufficiently strong and of sufficient duration to reach the cortex and activate the pyramidal neurons (which have very long connections linking different, distant parts of the brain), then boom! It’s the ignition 🚀! The information is now accessible to all cerebral areas (right).

Those two regimes are clearly distinct, according to Dehaene.

The Global Workspace Theory

These phenomena have been systematized in what is known as the “Global Workspace Theory,” which partly explains how information circulates in the brain: Information is transmitted from the visual area to the language area, and we find back the reportability criterion!

Incredible! We can now understand some conditions for humans to say, “I saw the signal!”.

So that’s it. Problem solved, isn’t it?

Nah, I’m still unhappy: this solves the problem of access consciousness but not phenomenal consciousness.

Moreover, when I looked at the lines of code in Dehaene’s simulations of the global workspace, I couldn’t convince myself that this code exhibited consciousness: He built a simulation, but his simulation is clearly not conscious. Besides, the Global Workspace Theory is just one theory among many, and there are plenty of others.

So, I continued my quest for theories of consciousness.

Integrated Information Theory

IIT: The above diagram illustrates the five axioms.

Why not try to formalize consciousness mathematically?

This is what integrated information theory proposes: we can start from 5 axioms based on our phenomenal experience and try to define a metric, a score of consciousness.

According to IIT, for a system to be conscious, it must be capable of integrating information under specific properties. Consciousness is the intrinsic capacity of a neural network to influence itself, determined by the maximum level of integrated information admitted by this network.

Each of these axioms measures a property of graphs, which are mathematical objects made up of a set of nodes and edges connecting the nodes. For example, we have eight nodes above.

  • On the left, the graph is complete: each node is connected to 7 other nodes.

  • On the right, the graph comprises 4 unconnected parts, so it is not very integrated, and the system will have a correspondingly small Phi.

Phi is a number that sums up the five properties. You could say that it’s like multiplying the score of the five properties, and you get a number:

Then we can imagine something like the following graph:

On the x-axis, different objects, such as a computer and a brain, that can be converted into the formalism of a graph. For each of these graphs, we can calculate a Phi.

But now, since we have a continuous metric, they need to define a threshold between what is conscious and what is not conscious.

But this threshold-setting operation is mathematically super ugly and arbitrary.

But on the other hand, if you don’t set a threshold, everything is a bit conscious. For example… even a carrot would be minimally conscious. WTF

IIT ad hoc statistics: Hum, interesting axiomatic, but doesn’t this imply panpsychism??

My understanding of the problem is that if we take this axiomatic, everything becomes at least minimally conscious, and that’s where we can sink into panpsychism.

Here’s an artist’s view of panpsychism: Everything in the universe is conscious, I’m conscious, you’re conscious, and so are cabbages and carrots. Fantastic!

Another problem with this theory is that it bites its own tail: IIT uses a mathematical formalism, the graph formalism, but it’s not easy to construct graphs from observations of the universe and to say what is information processing and what does not seem to depend on an observer.

For example: is the glass on my table an information processing system? No? However, glass is a band-pass filter for visible light and filters out ultraviolet light. Does that mean that the glass is minimally conscious?

Consciousness is the way information feels when it’s processed? Bro, who tells what/​where is/​isn’t information?

The list of criteria method

A list of 17 criteria for pain perception, taken from (Walters 2018)

Okay, we’ve seen GWT and IIT. I’d like to talk about one last method, which I call the list of criteria method.

For example, in the above image, you have a list of criteria for the perception of suffering, and in particular, in animals, we can study the criteria that allow us to know whether animals feel pain or not.

That’s the best method Science has been able to give us.

But even if this is the method used for animals, I didn’t find it satisfactory, and I have the impression that it still doesn’t solve the hard problem: lists are not elegant, and even if this is the SOTA method for pain assessment for animals, none of the items in the above list seemed to explain “what it’s like to feel suffering.”

Chapter 4: I’m lost

On the right: A philosophical zombie, atom for atom structurally identical to the man on the left.

It’s time to introduce an important concept: Philosophical Zombie.

The term philosophical zombie refers to a being that is physically and outwardly indistinguishable from a conscious being, both in behavior and in physical constitution, but which nevertheless has no awareness of its own existence or the world, no personal feelings or experiences.”

Although they behave as if they were experiencing emotions, zombies do not feel any, even though the biological and physical processes that determine their behavior are those of a person experiencing emotions.


To fully understand the philosophical zombie, we also need to introduce another notion: epiphenomenalism.

In the context of the philosophy of mind, epiphenomenalism is the thesis that mental phenomena (beliefs, desires, emotions, or intentions) have no causal power and, therefore, produce no effect on the body or on other mental phenomena [2].

For example, we can see that a physical state, P1, leads to a mental state, M1, and the physical state leads to a new physical state, P2, but mental states have no influence on the physical world.

We’re going to make a practical study of all this in a play:

[Pro Tip—I’ve presented this post during a talk, and during the presentation, I asked people to play different roles, and this was pretty effective in waking them up!]

From Zombies: The Movie — LessWrong :

FADE IN around a serious-looking group of uniformed military officers. At the head of the table, a senior, heavy-set man, GENERAL FRED, speaks.

GENERAL FRED: The reports are confirmed. New York has been overrun… by zombies.

COLONEL TODD: Again? But we just had a zombie invasion 28 days ago!

GENERAL FRED: These zombies… are different. They’re… philosophical zombies.

CAPTAIN MUDD: Are they filled with rage, causing them to bite people?

COLONEL TODD: Do they lose all capacity for reason?

GENERAL FRED: No. They behave… exactly like we do… except that they’re not conscious.

(Silence grips the table.)


GENERAL FRED moves over to a computerized display.

GENERAL FRED: This is New York City, two weeks ago.

The display shows crowds bustling through the streets, people eating in restaurants, a garbage truck hauling away trash.

GENERAL FRED: This… is New York City… now.

The display changes, showing a crowded subway train, a group of students laughing in a park, and a couple holding hands in the sunlight.

COLONEL TODD: It’s worse than I imagined.

CAPTAIN MUDD: How can you tell, exactly?

COLONEL TODD: I’ve never seen anything so brutally ordinary.

A lab-coated SCIENTIST stands up at the foot of the table.

SCIENTIST: The zombie disease eliminates consciousness without changing the brain in any way. We’ve been trying to understand how the disease is transmitted. Our conclusion is that, since the disease attacks dual properties of ordinary matter, it must, itself, operate outside our universe. We’re dealing with an epiphenomenal virus.

GENERAL FRED: Are you sure?

SCIENTIST: As sure as we can be in the total absence of evidence.

GENERAL FRED: All right. Compile a report on every epiphenomenon ever observed. What, where, and who. I want a list of everything that hasn’t happened in the last fifty years.

CAPTAIN MUDD: If the virus is epiphenomenal, how do we know it exists?

SCIENTIST: The same way we know we’re conscious.


GENERAL FRED: Have the doctors made any progress on finding an epiphenomenal cure?

SCIENTIST: They’ve tried every placebo in the book. No dice. Everything they do has an effect.


Great! This text by Yudkowsky has convinced me that the Philosophical Zombie thought experiment leads only to epiphenomenalism and must be avoided at all costs.

Did I become a materialist after that? No.

I could not be totally “deconfused” about consciousness, why? Mainly because of the following paper by Eric Schwitzgebel:

If Materialism Is True, the United States Is Probably Conscious

Eric Schwitzgebel

Philosophical Studies (2015) 172, 1697-1721

From the abstract: “If we set aside our morphological prejudices against spatially distributed group entities, we can see that the United States has all the types of properties that materialists tend to regard as characteristic of conscious beings.

So what Eric Schwitzgebel does in this paper is that he lists many properties that materialists say are necessary for consciousness. And he tells us, OK, look at the US that seems to have all the properties that you say are important for consciousness. So, in the end, wouldn’t the United States also be conscious if you put aside your bias against entities that are spatially distributed?

And I must say that the paper is convincing. It really gave me a lot of doubts.

Ultimately, I am left without a coherent position on the nature of consciousness. The more I explore the philosophical arguments and thought experiments, the more I find myself questioning the foundations of both materialist and non-materialist theories. It seems that each approach, when pushed to its logical limits, leads to conclusions that are difficult to accept. This leaves me in a state of philosophical deep uncertainty.

After a while, I even went mad because I couldn’t explain consciousness. I see it in myself, but I can’t explain it in any way. Maybe the only consciousness in the universe is mine, and that’s when I came across the wonderful philosophy of solipsism.

It doesn’t make sense; maybe the universe is only generated for me ?? in my head. Source
Solipsism: Am I alone? Why not man

I also began to devour podcasts and interviews, each more contradictory than the last. I particularly enjoyed Robert Lawrence Kuhn’s channel, which interviews different philosophers with radically different views in the same episode.

Closer to Truth: Damn, nobody knows shit, but Robert Lawrence Kuhn is my man.

Chapter 5: Moral Helpnesness

Here, I’d like to take a little detour into morality before the resolution.

It seems to me that consciousness is an important criterion for defining moral agents (in particular, valence, the ability to feel pain and pleasure, two dimensions of consciousness). (Yes, I was an essentialist in this regard)

After a while, I said to myself that we don’t understand anything about consciousness. Perhaps consciousness is not at all correlated to intelligence. Indeed, cows and fish are less intelligent than humans in many respects, but they have the fundamental ability to feel suffering, and it’s hard to say for sure that ‘there is nothing it is like to be a fish.’ So, let’s go for it; let’s become vegan.

We don’t know shit, let’s become vegan.

That’s when I came across Brian Tomasik’s blog, which explains that we should “minimize walking on the grass” to minimize insect suffering. And I’ve also stumbled upon the People for the Ethical Treatment of Reinforcement Learners. Promoting moral consideration for simple reinforcement learning algorithms. Then I also sympathized with Blake Lemoine, that Google engineer who said that language models are conscious, and I didn’t feel much further ahead than he did.

Google’s Lambda Polemic: I feel you, my friend; this is not a simple topic

I was maximally confused.

But I continued my research. In particular, I discovered the Qualia Research Institute, which was trying to better understand consciousness through meditation and the study of psychedelic states. I thought that their Qualia formalism was the only path forward. And I was not convinced by everything, but at least this view seemed coherent.

I knew most people on Lesswrong and Yudkowsky were eliminativists, but I was not able to fully understand/​feel this position.

What? Yudkowsky thinks animals who are not able to pass the mirror test are not really conscious? He thinks babies are not conscious? He thinks he’s not always conscious?? The mind projection fallacy is stronger than I thought.[3]

Chapter 6: Doubts

I’ve discussed the hard problem with a lot of people, and a lot of them were not familiar with it at all. Worse, they were not even able to understand it. Either I’m the only one conscious, either they are not phenomenally conscious, or they are not sufficiently intelligent to understand my pointer (or maybe I was explaining it badly?).

Or maybe the hard problem only exists in my head; is it an illusion or a wrong framing?

I began to doubt the existence of this hard problem

I’ve heard many people say, “The notion of consciousness will one day be deconstructed in the same way as we deconstructed the notion of Life.”

Indeed, there’s no single property that defines Life; it’s rather a list of properties: reproduction and evolution, survival, and remaining in a state of good working order, but no property is sufficient in itself.

I wasn’t convinced, but I said to myself, “OK, why not? Let’s see what happens if we say that consciousness is a list of properties.” I was a little disappointed because I don’t find this method very elegant, but hey, let’s give it a try.

This was a necessary leap of faith.

In addition, I began to take Yudkowsky’s article from Philosophical Zombies earlier more seriously. In particular, I wondered whether his text couldn’t be applied to the hard problem.

What is Consciousness? — Information is Beautiful

Take a look at the above image, which sums up the different theories of consciousness.

You may be familiar with the Anna Karenina principle: “All happy families are alike, but each unhappy family is unhappy in its own way.” Well, I thought it’s a bit the same with theories of consciousness: when we say: “Yo, the hard problem of consciousness exists,” and then we try to patch this problem, it brings up lots of very complicated and different theories, whereas if we say: “there’s no hard problem”, well, it’s much simpler.

many of them shared my concerns, almost precisely, but my own ideas from other lips sounded obsessive and ill-conceived.

Greg Egan, Learning to Be Me

Another piece of the puzzle is the blog post by Andrew Critch: Consciousness as a conflationnary alliance term. In summary, consciousness is a very loaded/​bloated/​fuzzy word, people don’t mean the same thing when talking about it.

Here’s a list of possible definitions encountered by Critch when asking people:

  1. (n≈3) Consciousness as introspection. Parts of my mind are able to look at other parts of my mind and think about them. That process is consciousness. Not all beings have this, but I do, and I consider it valuable.
    Note: people with this answer tended to have shorter conversations with me than the others, because the idea was simpler to explain than most of the other answers.

  2. (n≈3) Consciousness as purposefulness. There is a sense that one’s life has meaning, or purpose, and that the pursuit of that purpose is self-evidently valuable. Consciousness is a deep the experience of that self-evident value, or what religions might call the experience of having a soul. This is consciousness. Probably not all beings have this, and maybe not even all people, but I definitely do, and I consider it valuable.

  3. (n≈2) Consciousness as experiential coherence. I have a subjective sense that my experience at any moment is a coherent whole, where each part is related or connectable to every other part. This integration of experience into a coherent whole is consciousness.

So maybe consciousness has always been a linguistic debate?

Or you can make a whole list of criteria!

For example, here’s a list of some theoretical properties. We’ve just seen GWT and IIT, but there are plenty of others:

”Theoretical properties” (source)

There are also behavioral properties of progressive abstraction: from the low-level features like basic sensation or vibrotactile sensations to more and more abstract features like memory, intentionality, and imagination, and finally, fairly high-level features like language, meta-cognition, introspection, theory of mind, etc… This is like stacking cognition bricks:

“behavioral” properties (source)

The great thing about lists is that you can zoom in on an item, and if you look at one of these properties in isolation, it’s no longer mysterious. You can reimplement each of these properties with AIs.

For example, let’s take meta-cognition. The paper “LLMs mostly know what they know” shows that LLMs have some metacognition; they know what they know, and it’s possible to train models to predict the probability that they know the answer to a question.

As a result, I didn’t think that metacognition was mysterious anymore.

And this is not just for metacognition: I think you can reimplement/​understand all the other items in the preceding lists.

Here we are.

Chapter 7: Eureka!

Chapter 7: Eureka: The hard problem is a virus! And some people don’t have the virus :)

At parties, I was a super propagator of a virus that made people waste a lot of time on this problem.

Charbel, colorized, circa 2021

The Meta problem

[if this subpart doesn’t click, don’t stop, just continue to the next subsection]

To explain this virus, I suggest we consider the metaproblem of consciousness. The meta-problem consists of explaining why we think consciousness is a difficult problem.

Tl;dr, the meta-problem consists in explaining why we think consciousness is a difficult problem or, in other words, why we think consciousness is difficult to explain.

Nate Soares has given some answers to this problem and a large part of the ‘distilled’ solution is contained in this comment:

“[...]. Don’t start by asking ‘what is consciousness’ or ‘what are qualia’; start by asking ‘what are the cognitive causes of people talking about consciousness and qualia’, because while abstractions like ‘consciousness’ and ‘qualia’ might turn out to be labels for our own confusions, the words people emit about them are physical observations that won’t disappear. Once one has figured out what is going on, they can plausibly rescue the notions of ‘qualia’ and ‘consciousness’, though their concepts might look fundamentally different, just as a physicist’s concept of ‘heat’ may differ from that of a layperson. Having done this exercise at least in part, I [...] assert that consciousness/​qualia can be more-or-less rescued, and that there is a long list of things an algorithm has to do to ‘be conscious’ /​ ‘have qualia’ in the rescued sense. The mirror test seems to me like a decent proxy for at least one item on that list (and the presence of one might correlate with a handful of others, especially among animals with similar architectures to ours). [...] ”

The quest to unravel the mystery of consciousness involves not just defining the term but reconstructing the entire causal chain that leads some people to speak about it, why we utter the word “con-scious-ness”—to understand why, for example, my lips articulate this word.

If we can fully map this causal chain, we can then anticipate the circumstances in which people discuss “consciousness”. The various aspects of consciousness, enumerated in the lists seen earlier, are each useful concepts along this causal path.

By untangling this complexity, it becomes possible to redefine the notions of “qualia” and “consciousness”. It’s a bit like the term “heat”, which is perceived differently by a physicist and a non-specialist. Nate continues:

“[...] The type of knowledge I claim to have, is knowledge of (at least many components of) a cognitive algorithm that looks to me like it codes for consciousness, in the sense that if you were to execute it then it would claim to have qualia for transparent reasons and for the same reasons that humans do, and to be correct about that claim in the same way that we are. From this epistemic vantage point, I can indeed see clearly that consciousness is not much intertwined with predictive processing, nor with the “binding problem”, etc. I have not named the long list of components that I have compiled, and you, who lack such a list, may well not be able to tell what consciousness is or isn’t intertwined with. However, you can still perhaps understand what it would feel like to believe you can see (at least a good part of) such an algorithm, and perhaps this will help you understand my confidence. Many things look a lot more certain, and a lot less confusing, once you begin to see how to program them.”

The creation of a list of criteria is a crucial step; the list must be sufficiently elaborate to explain, among other things, why philosophers articulate with their lips the word “con-scious-ness” and pronounce syllable by syllable the expression “hard-pro-blem”.

I would argue that the lists seen above are good summaries of what consciousness corresponds to under the prism of the meta-problem.

Clustering is hard

The clustering algorithm in machine learning

Maybe becoming an expert in ML was not entirely for nothing.

There is an important algorithm in machine learning called the clustering algorithm. We give the algorithm the position on the x and y axis of all the points, and then the algorithm will say, “Okay, we have three clusters here, or two clusters, or one cluster, or lots of clusters.” That’s the clustering algorithm.

Sometimes, it is easy to determine the different clusters. For example, in the above image, there are clearly three clusters.

But sometimes it is much more difficult:

How many clusters? We don’t care

Clustering depends on an algorithm, and this algorithm is completely arbitrary. There is no single algorithm that solves all clustering problems. It’s really a problem that is not solved in machine learning and that won’t be solved, and there is no unique solution to this problem in full generality.

In the above image, clustering is going to be completely arbitrary.

Once we have done this work, we say that there is a cluster here, a cluster here, a cluster here, and we can give them names. For example, I can say, “Ah, the cluster that is in the top right, I will say that it is the north cluster.” I can give names, and labels to these different clusters. This is how human beings have evolved language: “All these things are trees, all these things are reflexes. All these things are chairs. All these things are memory. All these things are consciousness”. We can give names to things, but ultimately, intrinsically, what happens is that we see different phenomena, and we cluster them in the brain. Different neurons will react to different clusters, and we will have a neuron that will be associated with each cluster.

Alice and Bob are different clustering algorithms. Source

So here, I’m showing you a little bit different clustering algorithms. We have different clouds of points and different clustering algorithms, and different clustering algorithms will not necessarily give the same answers.

For example, in one column, we have the Bob algorithm, and in another column, the Alice algorithm, each of the individuals, each of the people in the street that Andrew Critch interviewed earlier.

For consciousness, we have this pyramid of capacities:

We have different points here, and then we have to cluster these capacities and name them.

There are people who will say, “Okay, consciousness is just that,” and they will make a circle on the top of the pyramid, or they will say, “That’s consciousness!” and they will draw a giant circle. Then, there are people who will say, “No, what interests me more is sentience.” They will say, “Okay, we will make a circle here in the bottom, near the basic somatosensory stuff,” and they will say that’s sentience.

The problem is completely ill-defined.

So, people will see the same capacities and name things differently. But you see that the problem is not very well posed. Finally, what matters more is what the territory looks like, and what the different capacities that are underlying look like.


Figure: Peak interpretability, the car detector (source)

This is an image that I really like. An image that was found by Chris Olah when he studied the circuits in image recognition neural networks. What his team found is that the car neuron is connected to three neurons that are lower level than the car neuron. For this image classifier, a car is actually a window, a body, and wheels that are each, respectively, at the top, middle, and bottom, and when the three neurons are activated, the car neuron is activated. That’s how neural networks work for vision. (Obviously, this is a simplification).

Why am I talking about this kind of thing?

Well, obviously, because your brain is also a neural network, there are also neurons, and so there is an algorithm that allows us to say whether something is conscious or not.

Whatever + stuff + Youhou → Consciousness. But I don’t care if your “Consciousness” neuron is firing or not. I care about the low-level features.

And maybe your algorithm is, “Okay, there is memory, language, or reasoning, and boom, this is consciousness”. Or maybe it’s an algorithm that is totally different; for example, when you hurt a dog, it has a reflex, and so, here, you can substitute reasoning for reflex, etc. And that gives you another notion of consciousness. But in the end, what happened is that during your learning, you saw the word consciousness associated with different things. And then, what happened in your brain is that these different things, that appeared next to the word consciousness assembled with each other. This assembly is different from one person to another, and that’s why, then, different people will associate the consciousness neuron with different properties.

And at the end of the day, I don’t think there is much difference between the problem of consciousness and the sorites paradox:

The sorites paradox: If a heap is reduced by a single grain at a time, at what exact point does it cease to be considered a heap?

And what I’m saying here applies to the word consciousness, it applies to the word sentience, it applies to a lot of other things.

The ghost argument

Imagine a child who believes that ghosts haunt his house every night before he goes to sleep, even though he’s old enough to understand rationally that ghosts don’t exist. Although he knows that everything can be explained without resorting to the idea of ghosts, he nevertheless feels their presence. It could be said that a specific neuron in his brain is intensely activated, associated with the notion of a ghost when he experiences fear. As he grows older, the child gradually begins to convince himself that ghosts don’t exist, adopting a more rational approach to the world. Gradually, the “ghost neuron” ceases to be stimulated and begins synaptic pruning, and this natural process gradually weakens and eliminates the synaptic connections associated with his fear of ghosts.

This is similar to the hard problem of consciousness. There is a neuron (or a representation) in the brain linked to the idea of a dualistic world, divided between matter and thought. But this framework of thought leads nowhere: and it is necessary to deliberately choose to stop thinking in this representation in order to stop being struck by the sensation that this problem exists.

This is consistent with people not falling into this framing and not being confused by the problem at all.

To stop being afraid of the dark, your neuron of the Ghost needs to go away, but that is not a simple cognitive move. It’s even almost impossible to do it by force, you just need to be patient.

To stop being confused by the Hard problem, your neural representations with the explanatory gap need to be pruned; That’s not a simple cognitive move. That’s like an anti-leap of faith.

But this is a salutary move that you can train yourself to make to stop believing in God, to stop believing in ghosts, to stop believing in vitalism, etc…

A new theory of Impact for Interpretability: In this figure, we can see that Anthropic is able to intervene in neurons and change the behavior of LLMs. Maybe in the future, we will be able to do brain surgery on humans to remove the activation from the “hard problem” neuron, but you will have to meditate on this post until then. Figure from the dictionary learning paper.

Chapter 8: Digital Sentience

If we reuse the pyramid to see which features GPT-4 exhibits, we get this:

It’s no longer a pyramid, it’s a Swiss cheese with many holes

Is GPT-4 phenomenally conscious? Is a table without feet still a table? Is a carrot that is blue still a carrot? Are viruses part of life? I’m not interested in those questions.

What’s really interesting is that we can see with AIs that the different sub-features of cognition can appear completely independently of each other, in different AIs. There really are many degrees of freedom.

And I’m much more interested in questions like: “Is the AI able of Auto Replication and Adaption”.

So that’s my position: I’m an eliminativist. I think we should eliminate the world consciousness and focus on the lower-level features. And I think the hard problem is a virus.

I hope this presentation can act as a vaccine, and save you some time.

Solving the meta-problem: A methodology to reconstruct cleanly the notion of consciousness for AIs

Nate Soares says: “Having done this exercise at least in part, I [...] assert that consciousness/​qualia can be more-or-less rescued, and that there is a long list of things an algorithm has to do to ‘be conscious’ /​ ‘have qualia’ in the rescued sense.

Here is a methodology that enables to reconstruct such a list.

We’ll again approach the question of digital sentience through this new prism of the meta-problem, i.e. being able to explain why AIs would talk about consciousness.

There’s a problem in digital sentience, and it’s called the Gaming problem: AIs can talk about consciousness but only repeat like parrots what they’ve seen in the dataset.

Fortunately, there’s a solution to this problem:

We simulate AIs talking about philosophy. The AIs in the simulation initially don’t know what consciousness is. We filter out anything that talks about consciousness in the training texts and see if the philosopher AIs start to invent the notion of a hard problem after a while in the simulation.

I define “being conscious” as “being able to reinvent the hard problem of consciousness”. Note that this is an arbitrary criterion, but that this criterion is much stricter than what we ask of humans. Most people are not at the level of David Chalmers who was able to invent the meme by himself.

If they do reinvent the hard problem, it would be a big sign that the AIs in the simulation are “conscious” (in the reconstructed sense).

I assert that this experiment would solve the hard problem, because we could look at the logs,[4] and the entire causal history of the AI that utters the words “Hard pro-ble-m of Con-scious-ness” would be understandable. Everything would just be plainly understandable mechanistically, and David Chalmer would need to surrender.

What’s more, I claim we’ll be able to create such a working simulation in the future (even if I don’t technically justify this here).

It was clear to me by then that nobody had the answers I craved — and I was hardly likely to come up with them myself; my intellectual skills were, at best, mediocre. It came down to a simple choice: I could waste time fretting about the mysteries of consciousness, or, like everybody else, I could stop worrying and get on with my life.

--- From Greg Egan, Learning to Be Me.

Thanks heaps to everyone who helped me along the way, especially people who posted some thoughts online.

Further Exploration

Here are some additional references:

  • For everyone: Explore major milestones in the Theory of consciousness in the Lesswrong Wiki: Consciousness—Lesswrong Wiki

  • If you are still confused,If my intuition pumps were not sufficient, you should:

  • If you agree with this post: For an in-depth scholarly approach, consider reading Luke Muehlhauser’s 2017 Report on Consciousness and Moral Patienthood. This is a substantial piece of work by the rationality community, delving into consciousness. It’s advanced material, presupposing concepts like physicalism, functionalism, illusionism, and a fuzzy view of consciousness.

  • If you want to discover another perspective, The Qualia Research Institute offers a unique perspective. While their metaphysical standpoint might be debatable, their research is undeniably intriguing and explores different sub-dimensions of awareness. Recommended viewings include their presentations at the Harvard Science of Psychedelics Club: The Hyperbolic Geometry of DMT Experiences, and Logarithmic Scales of Pleasure and Pain, which are cool phenomena that remain to be fully understood in the meta-problem prisms.

Addendum: AI Safety & Situational Awareness

As I said in the beginning, I think it’s beneficial to be deconfused about consciousness for conceptual research in AI Safety. When I present in class the emerging capabilities of AI models that could pose problems, I often cite those given in the paper ‘Model Evaluation for Extreme Risks,’ such as cyber-offense, manipulation, deception, weapon acquisition, long horizon planning, AI development, situational awareness, and self-proliferation. After explaining each of these capabilities, I am often asked the following question: ‘But hum… Situational Awareness is strange because that would mean that the model is conscious. Is that possible?

Damn. How to give a good answer in a limited time?

Here is the answer I often give:

Good question!

I think it’s better not to use the word consciousness for now, which will take us too far.

Let’s calmly return to the definition of situational awareness. If we simplify, situational awareness literally means ‘being aware of the situation,’ that is, being able to use contextual information related to the situation. For example, time or geographic position are contextual information. Models will be selected to use this information because they perform better if they can use it, for example, for automatic package delivery.

For instance, I am situationally aware because I know my first name, I know that I am a human; when I was little, I read that humans are made up of cells that contain DNA. All this contextual information about myself allows me to be more competent.

In the same way, AIs will be selected to be competent and to be able to use information about their situation will be selected. It’s not that mysterious.

One variable that matters for situational awareness is knowing if someone is observing you at a given moment. Children learn very quickly to behave differently depending on whether they are observed or not; in the same way, an AI could also adopt different behaviors depending on whether it knows it is being observed or not.

And, of course, situational awareness is not binary. A child has less SA than an adult.

Situational awareness can be broken down into many sub-dimensions, and a recent paper shows that LLMs exhibit emerging signals of situational awareness.

from Berglund et al. (2023)

Just as the word ‘intelligence’ is not monolithic, and it is better to study the different dimensions of the AI capabilities spectrum (as suggested by Victoria Krakovna in ‘When discussing AI risks, talk about capabilities, not intelligence’), I think we should avoid using the word ‘consciousness’ and talk about the different capabilities, including the different dimensions of situational awareness capacities of AIs.”

Addendum: From Pain to Meta-Ethics

What is pain? Why is pain bad?

It’s the same trick: we shouldn’t ask, “Why is pain negative,” but “Why do we think pain is negative?” Here’s the response in the form of a genealogy of morals:

  • Detectors for intense heat are extremely useful. Organisms without these detectors are replaced by those who react reflexively to heat. Muscle fatigue detectors are also extremely useful: Organisms without these detectors are replaced by those that react to these signals and conserve their muscle tissue. The same goes for the dangerous mechanical and chemical stimulation conveyed by type-C fibers.

  • In the brain, the brain constantly processes different signals. However, signals from type-C fibers are hard-coded as high-priority signals. The brain’s attention then focuses on these signals, and in cases of severe pain, it’s impossible to focus on anything else.

  • Next, we start to moan, scream, and cry to alert other tribe members that we are in trouble.

  • There are many different forms of suffering: Physical Pain, Emotional Suffering, Psychological Trauma, Existential Anguish, Suffering from Loss, Chronic Illnesses, and Addiction. Suffering is a broad term that includes various phenomena. However, at its core, it refers to states that individuals could choose to remove if given the option.

  • If you concentrate sufficiently on pain and are able to deconstruct it dimension by dimension, feature by feature, you will understand that it’s a cluster of sensations not that different from other sensations. If you go through this process, you can even become like a Buddhist monk who is able to self-immolate without suffering.

  • At the end of the day, asking why pain is bad is tautological. “Bad” is a label that was created to describe a cluster of things that should be avoided, including pain.

What is Ethics?

We can continue the previous story:

  • Values: In the previous story, the tribe organizes itself by common values, and tribe members must learn these values to be good members of the tribe. Tribes coordinated through these values/​rules/​laws/​protocols are tribes that survive longer. The village elder, stroking his beard, says: “Ah, X1 is good, X2 is bad.” This statement transmits the illusion of morality to the tribe members. It is a necessary illusion that is shared by the members of the tribe in order for the tribe to function effectively. It can be thought of as a mental meme, a software downloaded into the minds of individuals that guides their behavior appropriately.

  • Prophets and Philosophers then attempt to systematize this process by asking, “What criteria determine the goodness of X?” They create ad hoc verbal rules that align with the training dataset X1, X2, … XN, Y1, Y2, …,YN. One rule that fits the dataset reasonably well is ‘Don’t kill people of your own tribe’. That gets written in the holy book alongside other poor heuristics.

  • Flourishing Arab civilization: Merchants invent trade, and then mathematicians invent money! It’s really great to assign numbers to things, as it facilitates commerce.

  • Ethicists: Philosophers familiar with the use of numbers then try to assign values to different aspects of the world: “X1 is worth 3 utils! X2 is worth 5 utils!”. They call themselves utilitarians. Philosophers who are less happy with the use of numbers prefer sticking to hardcoded rules. They call themselves Deontologists. They often engage in arguments with each other.

  • Meta-ethicists: Philosophers who are witnessing disagreements among philosophers about what is the best system start writing about meta-ethics. Much of what they say is meh.[5] Just as the majority of intellectual production in theology is done by people who are confused about the nature of the world, it seems to me that the majority of intellectual production in moral philosophy is done by people who are self-selected to spend years on those problems.

And note that I’ve never crossed Hume’s guillotine during the story, which was my answer to the meta-problem of pain.

  1. ^

    For those who are wondering, the number is 4 on the bottom left, and there is no number on the top right.

  2. ^

    It’s called epiphenomenalism because mental phenomena are interpreted as epiphenomena, i.e., phenomena generated by the brain but which have no feedback effect on it.

  3. ^

    Yud also says: If there were no health reason to eat cows I would not eat them

  4. ^

    Look at the logs, or use inference functions

  5. ^

    Go read this SEP article if you don’t believe me.