(2023-08-30) Hoel Consciousness Is A Great Mystery: Its Definition Isn't

Erik Hoel: Consciousness is a great mystery. Its definition isn't. *There’s an unkillable myth that the very definition of the word “consciousness” is somehow so slippery, so bedeviled with problems, that we must first specify what we mean out of ten different notions. When this definitional objection is raised, its implicit point is often—not always, but often—that the people who wish to study consciousness scientifically (or philosophically) are so fundamentally confused they can’t even agree on a definition. And if a definition cannot be agreed upon, we should question whether there is anything to say at all.

at least linguistically, “consciousness” is well-defined, and that this isn’t really a matter of opinion. Most experts... have an agreed-upon vocabulary concerning terms and definitions in the field, which definitely includes “consciousness” broadly. Another way to say it: if you walk around The Association for the Scientific Study of Consciousness, which brings together hundreds of neuroscientists and philosophers annually to share their research, you will find little definitional confusion over “consciousness.”

(this is) very different than saying you should blindly believe the conclusions of that field.

So, what’s the agreed-upon definition of the word “consciousness?” Essentially, it’s a definition best given in Thomas Nagel’s 1974 famous philosophy paper “What it is like to be a bat?”

there is something it is like to be that organism.”

Nagel’s definition is what has gained widespread adoption by those in philosophy of mind as well as the neuroscience of consciousness.

Erik Hoel: “Consciousness is what is like to be you. It is the set of experiences, emotions, sensations, and thoughts that occupy your day, at the center of which is always you, the experiencer. You lose consciousness when you go under anesthesia and when in a dreamless sleep, and you gain consciousness when you wake up in the morning or come up from anesthesia.”

Giulio Tononi (prominent neuroscientist, originator of the Integrated Information Theory of consciousness): “Consciousness is everything we experience. Think of it as what abandons us every night when we fall into dreamless sleep and returns the next morning when we wake up. Without consciousness, as far as we are concerned, there would be neither an external world nor our own selves: there would be nothing at all.

Anil Seth (prominent neuroscientist): “Consciousness is the most familiar thing for any of us. . . . Consciousness is any kind of experience at all, whether it's a visual experience of the world around us, whether it's an emotional experience of feeling sad or jealousy or happy or excited. . . . consciousness is the word that we use to circumscribe all the different kinds of experiences that we can have.

older figures, like William James, one of the founders of psychology, are also obviously referring to the same phenomena as well.
William James: “The first and foremost concrete fact which every one will affirm to belong to his inner experience is the fact that consciousness of some sort goes on.

Perhaps all these definitions seem quite broad and mysterious. That’s very fair! But certainly they all seem to be pointing at the same phenomenon to investigate.

Additionally, there are further well-accepted definitional breakdowns that emphasize different aspects of consciousness

Specifically, the dynamic and cognitive aspect of consciousness is often distinguished from the qualitative what-it-is-likeness of consciousness. There are a few different ways to discuss this. The most favored is to refer to “qualia” as the distinct experiential what-it-is-like quality of consciousness (“the redness of red”).

This leads to differentiations like that of philosopher David Chalmers, who distinguished between the “easy problem” of consciousness (essentially, how consciousness works as a cognitive act) and the “hard problem” (where do qualia come from?).

There are also breakdowns of the definition of consciousness along other dimensions, like how complex different consciousnesses can be. E.g. Nobel Prize winner Gerald Edelman, one of the founders of the field of consciousness research, distinguished between “primary consciousness” and “secondary consciousness.” Primary consciousness would be the simple sensations and experiences of consciousness, like perception and emotion, while secondary consciousness would be the higher-order aspects, like self-awareness and meta-cognition. A dog would (likely) have primary consciousness (there is something it is like to be your dog) but it would lack secondary consciousness (their consciousness is not as richly self-aware as ours, they never have an internal narration, and so on)

And finally, there is the level of consciousness, which is mainly a medical term. The level of consciousness is a common and agreed-upon scale that can distinguish between, e.g., a vegetative state, someone with locked-in syndrome, or a coma

these definitions don’t these tell us what consciousness actually is, no?

Both these objections might be true, but they also don’t matter at all

there is a difference between a naive definition of a phenomenon and a scientific definition of that same phenomenon.

imagine for a moment that Isaac Newton asked for a glass of water. Now, this is before the molecular composition of water had been discovered. So Newton does not know that water = H2O (the scientific definition of water). Still, when Isaac Newton says the word “water” he means something quite specific, even if his is a naive definition

It would be sophistry to say that, because the scientific definition had not yet been discovered, Newton does not have any idea of what he means by “water.

So while there’s no agreement on what consciousness actually is from a scientific perspective, that’s totally fine, since what matters is whether researchers and scientists are referring to the same thing. Whether when they point, their fingers (abstractly) target the same phenomenon.

The final resort of the definitional critique would be to say that, fine, there is a shared naive definition, but that definition is not itself precise enough to allow for scientific, philosophical, or technological progress

I think this ends up being quite a difficult argument to make.

First, there would need to be strong evidence that our definition of “consciousness” is indeed weaker than naive pre-scientific definitions of other phenomena

Second, the idea that definitions are the problem is contradicted by all sorts of evidence from the field itself. E.g., just recently, the neuroscientist Christof Koch this summer conceded a 25-year bet to the philosopher David Chalmers that we would find a clear neural correlate of consciousness by now (we haven’t).
Both Chalmers and Koch would know a neural correlate if they saw it, and are happy to agree they both don’t see one.

Another recent example: Giulio Tononi and Bernard Baars are the originators of the two leading scientific theories of consciousness, Integrated Information Theory and Global Workspace Theory, respectively. As reported by The New York Times:. . . the Templeton World Charity Foundation has begun supporting large-scale studies that put different pairs of theories in a head-to-head test, in a process called adversarial collaboration.
And last month, researchers at the New York event unveiled the results of the foundation’s first trial, a matchup of two of the most prominent theories.
The two theories made different predictions about which patterns the scientists would see. According to the Global Workspace Theory, the clearest signal would come from the prefrontal cortex because it broadcasts information across the brain. The Integrated Information Theory, on the other hand, predicted that regions with the most complex connections—those in the back of the brain—would be most active.

Dr. Melloni [one of the independent investigators] explained that in some tests there was a clear winner and a clear loser. The activity in the back of the brain endured through the entire time that volunteers saw an object, for example. Score one for the Integrated Information Theory. But in other tests, the Global Workspace Theory’s predictions were borne out.
In one sense, the adversarial collaboration was a bust, in that neither theory was fully falsified. But obviously the two teams could agree not just on definitions, but on experiments, differential predictions, analysis, all sorts of things.

A final note. Recently, some extra definitional confusion was thrown back into questions of consciousness. Specifically, there is now the highly relevant concern of whether or not contemporary AIs are conscious, or could be conscious in the future. (AGI)

“sentience,” in contrast to “consciousness,” is not a well-defined term. In my opinion, “sentience” is most similar to Edelman’s “secondary consciousness,” but regardless, it’s still not commonly used within the field of consciousness research

that naive definition is not enough

First, there are practical and business aspects: it highly likely that, e.g., true brain-machine interfaces will require a theory of consciousness to actually function reliably. But even more important: it is consciousness that gives an entity moral value.

We have no firm scientific basis for assigning consciousness to anything at all, from AIs to animals, and yet, so much of our morality is based on consciousness. We care about suffering, and joy, and seeking to minimize one and maximize the other.

Despite this being a scientific age, there is a funny sense in which we lack a scientific definition of what we value most: ourselves.