[♪♪♪] [♪♪♪] ROBERT LAWRENCE KUHN:<i>
Consciousness is odd.</i> <i> At once, most mundane
and most bizarre.</i> <i> Our astonishing inner sense
of awareness and feeling</i> <i> seems so radically alien.</i> <i>Nothing like the physical field,
forces, and particles</i> <i> that compose stars
and planets and even life.</i> <i> Consciousness is the most
mysterious feature of existence</i> <i> other than the mystery
of existence itself.</i> [man speaking indistinctly] <i> We seek the locus
of consciousness.</i> <i> What or where in the brain
causes consciousness?</i> <i> As an old neuroscientist,
that's what I sought, sort of.</i> <i> But then the realization...</i> <i> Even if one or more brain
regions is needed</i> <i> to be conscious,
that in no way explains</i> <i> what felt consciousness is
or how it happens.</i> <i> I'm skeptical, too,
about drilling down</i> <i> to the fundamental physics.</i> <i> Meaning in the brain seems
at the level of neurons</i> <i> and networks. So, I'm open.
I'm forced to be.</i> <i> I must ask, does consciousness
require a radical explanation?</i> <i> I'm Robert Lawrence Kuhn,</i> <i> and</i> Closer to Truth<i>
is my journey to find out.</i> [♪♪♪] <i> I should start with
a neuroscientist who has</i> <i> an innovative, indeed radical,
theory of consciousness,</i> <i> and I should hear about it
directly from him.</i> <i>He is a professor of psychiatry</i> <i> and an expert on sleep,
Giulio Tononi.</i> <i> I'd wanted to meet Giulio
for about a decade.</i> <i> Then I found he was attending</i> <i> the Foundational Questions
Institution, FQXi, conference</i> <i> in Vieques, Puerto Rico,
in 2014.</i> <i> I have been attending FQXi
conferences since they began.</i> <i>Exploring foundations of physics
and frontiers of cosmology,</i> <i> FQXi looks beyond
scientific horizons.</i> <i> The theme in Vieques
was information,</i> <i> and Giulio was a natural,</i> <i> extending FQXI's
intellectual vision.</i> <i> Meeting Giulio in the Vieques
jungles seemed to invite entry</i> <i> into the brain's
neural networks.</i> <i> But I sensed more.</i> Giulio, we've just met, but
we have something in common. We've both been obsessed with
consciousness our whole lives. Why is conscious so baffling? Because it's everything
we have, all we are. So, consciousness is
all we experience. And of course, if you eliminate
experience from everything else, nothing is left. It is important to study
the brain, but you will never squeeze
the essence of conscious out of grey matter. This is why philosophers
have rightly pointed out for a long time that this is
a very hard problem. In fact, this is so hard
that I grant you it is impossible
to solve that way. You need to take
a different approach. What is that approach? I think the approach is to go
exactly the other way around. Let's try to start from
consciousness itself. We have to identify what are
the essential properties of consciousness. What is it like to be a
person who has an experience. And that applies
to every experience you possibly could have. So, I call these the axioms
of consciousness. The first one is the one
that Descartes pointed out, that is that
consciousness exists. There is no doubt that you
are having an experience, but there are other fundamental
properties of every experience that one can think aloud. A very important one is that
every experience is structured. When I have an experience,
like, right now, I see you, I see your black shirt,
I see your grey hair, and I see the canopy
of the jungle here. When I see all of that, these are different aspects
of a single experience. Let's move to
a more intriguing one of the properties
of consciousness, which has been unrecognized even
by philosophers. And that is the fact that
every experience is what it is. Experience I am having
now is a very special one. I've never been in this jungle
before, I've never been with you, and I've never been in
a situation of this sort. And what makes this experience
that particular one is what I call information. Information from the intrinsic
perspective, from inside. It is what it is
because it differs from trillions and trillions of
other possible experiences I could have.
But I'm having this one. The next axiom is integration. And that is referring
to the fact that every experience is always one. You cannot decompose it
into non-interdependent parts. For instance,
the color of your shirt and the shape of your shirt, okay, I can't experience the
color and the shape separately. It doesn't even make sense. That's integration. And then we have one further
axiom which is exclusion that says that an
experience is only one. So, it's unique. There is not simultaneously
a superposition of many different experiences. So, what's the implication
of these axioms? The idea here is that if these
are essentially properties of consciousness such that there
cannot be an experience that doesn't obey
these axioms, we have to think of whatever
is out there in the world that can accurately account for
these properties. It must explain why this thing
that we have exists, why it is structured,
why it is informative, why it is integrated,
and why it is exclusive. Based on that, it says there
is a fundamental identity and experience,
the one you're having now, is a maximally reducible
conceptual structure, which is a long thing to say, but it has precise
mathematical meaning. In fact, it is a structure in
a space called qualia space. Think of it as a shape, but it
is a shape seen from the inside. And the idea is that right now,
there is a shape that is generated by a
particular part of your brain and not by many other parts. Are you saying that that shape
is my feeling of consciousness, my sense, my inner experience,
my personal phenomenology, or that is a correlate
or relates to it? No, it is.
It is an exact identity. It's an exact identity? To be that shape
is to have that experience. That can only be had
from the inside. You must be that thing. I cannot be you
and you cannot be me. Being is not describing. You cannot be what you describe, but you can describe
what you are. [♪♪♪] KUHN:<i> I'm elated,
not because I've signed on,</i> <i>but because a serious scientific
initiative recognizes</i> <i> that conscious is indeed
radically bizarre.</i> <i> Integrated information theory
is a bold, revolutionary way</i> <i> to explain the qualia
or inner feel of consciousness.</i> <i> The claim is that each unique
integrated conscious experience</i> <i> is a distinct thing,
a shape-like thing located</i> <i> in an utterly unknown kind
of dimensional space</i> <i> called qualia space.</i> <i> If explaining consciousness
is truly a hard problem,</i> <i> it follows that theories of
consciousness should be rejected</i> <i> not when they're too radical,</i> <i> but when they're not
radical enough.</i> <i> Giulio's theory
aces this first test.</i> <i> It is radical enough.</i> <i> I'm intrigued,
I want more.</i> [♪♪♪] <i> Two years later,
I get the chance.</i> <i> It's the next FQXi conference,
this time in Banff, Canada.</i> <i> Buffeted by the crisp winds
of the Rocky Mountains,</i> <i> I meet the philosopher of mind
who famously disrupted the field</i> <i> by coining the hard problem of
consciousness, Dave Chalmers.</i> <i>Dave has his own radical ideas.</i> There are a whole lot of at
least potentially intriguing connections between physics
and consciousness, and especially
quantum mechanics. Traditional formulations of
quantum mechanics seem to give a role to measurement
or observations, and well, what is that? And it's like, well, the natural
hypothesis is that measurements are, observation is
conscious perception. It's somehow a role
of a conscious observer. So, that's extremely suggestive
for connecting the two, but you can connect them
in a lot of ways. Some people might try to
reductionistically explain consciousness in terms of
quantum mechanical processes. In my view, that works no better
than explaining it in terms of classical processes. But another thing
you might do is not try to reduce consciousness, but
find roles for consciousness in quantum mechanics. And of course, one of the big
questions about consciousness is what does it do?
What is it here for? How can it affect
the physical world? All the harder a question
if you think consciousness is irreducible and fundamental. So, I'm at least taking
seriously the idea that maybe consciousness plays a potential
role in quantum mechanics. It's a version
of the traditional idea that consciousness collapses
the wave function. Not one thing has happened
in the last 20 years, as people have started to develop rigorous
non-reductionist theories of consciousness, like Tononi's
integrated information theory. So, lately I've been thinking
about the idea, maybe we could combine that with
a quantum mechanical theory of consciousness
collapsing the wave function. Integrated information theory
would give us the theory of when a certain physical state
gives rise to conscious. When it integrates enough
information, for example. Quantum mechanics would then
tell us when that happens, consciousness will collapse the
wave function in a certain way. And if we combine a mathematical
theory of consciousness with the traditional collapse
interpretation of quantum mechanics,
we might be able to get a mathematically rigorous
quantum mechanical approach to consciousness. If you do that though,
are you undermining the fundamental assertion
that consciousness is an irreducible, fundamental
part of reality, because integrated information
theory seems to be coming up with a mechanism
of creating consciousness when you have certain things
together, then you have consciousness. But in your view, you don't need
to bring things together to have the consciousness, because you have consciousness
at its most fundamental level. Yeah, I see these
as two different approaches. There's the panpsychist approach
where consciousness exists at the fundamental level
of physics and all that comes together
to yield me, and there's the dualist approach
where consciousness is separate from the physics
but interacts with it. And I see this quantum
mechanical idea we've been talking about
just now as a dualist idea rather than a panpsychist idea. We've got a wave function
and we've got consciousness as distinctive properties, and now here are the laws
that connect them. So, this view won't
work with panpsychism. If you want to think of this as
an updated version of Descartes. Body affects the mind,
the mind affects the body. Integrated information theory
tells us how physics affects consciousness. Collapse tells us how
consciousness affects physics. [♪♪♪] KUHN:<i> I'd love deep, structural
ties between consciousness</i> <i>and quantum mechanics, but not,
according to Dave,</i> <i> quantum mechanics explaining
consciousness,</i> <i> rather consciousness
being fundamental</i> <i> empowering quantum mechanics.</i> <i> I like Dave distinguishing
panpsychism,</i> <i> where consciousness somehow
resides in or below physics,</i> <i> from a kind of dualism where
consciousness and physics</i> <i> are equal and interact.</i> [indistinct conversation] <i> I'm hooked.</i> <i> But hooked to pursue,
not to believe,</i> <i> because most neuroscientists
still consider consciousness</i> <i> not as a special entity
to discover,</i> <i> but as a biological problem
to solve.</i> <i> I need a physicalist.</i> <i> One of the more fearsome,
whose engaging style masks</i> <i> a relentless logic, is also
attending the FQXi conference,</i> <i> theoretical physicist
Sean Carroll.</i> I think that consciousness
is a way of talking about the physical world, just like
many other ways of talking. It's one of these emergent
phenomena that we find as a useful way
of packaging reality. So, we say that someone
is conscious off something that corresponds to certain physical
actions in the real world. I don't think that there is
anything special about mental properties, I don't
think there's any special mental realm of existence. I think it's all
the physical world in all the manifold ways
we have of describing it. I would believe
that consciousness is qualitatively different, and
you must disagree with that. I do disagree. There's an irreducibility,
but it's not in the reality. It's in how people talk
to each other about it. - There's something that--
- But you see it, you live it, - you feel it.
- Of course, that's right. And I can describe it in
physical terms perfectly well. When you say, like, I now have
experienced the redness of red, I think that that is a set of
words that can be mapped on in a very direct way
to certain physical things happening in my brain. Do you believe that the
phenomenology of what we see is in an identical theory
sense two descriptions? Like, the morning star and the
evening star is the same... - Yes, that's right. Absolutely.
- Is Venus. And the difference between me
and someone who thinks that there is something
phenomenologically different about consciousness
is that that is all there is. [♪♪♪] KUHN:<i> Sean admits nothing
special about consciousness.</i> <i> And if consciousness
seems irreducible,</i> <i> the reason is human language
and culture,</i> <i> not any separate spooky kind
of non-physical reality.</i> I revel in the
sharp disagreement. [indistinct conversation] <i> I hear that some physicists
are taking a fresh look</i> <i> at consciousness.</i> <i> I meet my old friend, a
physicist who envisions reality</i> <i> as a mathematical object,
the Scientific Director of FQXi,</i> <i> cosmologist Max Tegmark.</i> A large fraction of the things
we're stuck on in physics, of the unsolved mysteries, actually have to do with what
it means to be an observer. And if you take, for example,
the biggest embarrassment of all, that we can't unify
general relativity, the theory of the big,
with quantum mechanics, the theory of the small,
these two theories have the exact opposite
definition of observer. General relativity says that
an observer is this infinitesimally tiny thing
with no mass and having no effect
on its environment. - A point, yeah.
- Yeah. Whereas quantum mechanics says
that the observer has an effect on that
which is observed. So, no wonder
we can't unify them. Where the rub lies, it's the
fact that we've tried to avoid talking about what an observer
is even though physics is supposed to be the subject
of observation, which is ridiculous. There's been this kind of
prejudice that consciousness is just a bunch
of flakey, hooey, that a physicist
shouldn't talk about it, and that we could somehow get
away with not talking about it. And I think we have to face
up to the fact now that no, especially if you believe that I
am made of quarks and electrons and physical things, I can't
sweep under the rug the fact that I am an observer, and if I
want to know what observers see, I have to understand the
relationship between quarks and electrons
and this subjective... If you take the famous hard
problem of [unintelligible], namely why is it that
this quark blob has a subjective experience,
that feels very hard. But if you take it as a starting
point, that some quark blobs, like this one,
have a subjective experience, and other ones like this table
don't, then this transforms the hard
problem into this hard fact, that some quark blobs are
consciousness, some aren't. So, there must be some physical
principle, some equation which tells you which things
are conscious and which aren't. And this becomes now
an experimental question. My guess is that
the subjective experience that we call consciousness
is the way information feels when being processed
in certain complex ways, and I feel I'm kind of forced
into guessing this from the starting point
that I think it's all physics. I'm not allowed to have any
extra secret sauce to add to it. And that makes it much harder
for me, but at the same time, it limits it down to this
very concrete problem that I have to ask. There is clearly some
additional principle about information processing
in nature that distinguishes between the conscious kind
and the unconscious kind, and I would love to find it. [♪♪♪] KUHN:<i>
Who wouldn't love to find it,</i> <i> the information processing it
that distinguishes</i> <i> the conscious from the
non-conscious, whatever it is.</i> <i> The choice seems stark.</i> <i> Either some new
mathematical description</i> <i> of how the world works,</i> <i> or some radically new
feature of reality.</i> <i> But hold on.</i> <i> Am I being swayed by
a self-selected subset</i> <i> of physicists and philosophers
who mystify consciousness?</i> <i> I should check the more
mainstream physicists</i> <i> and philosophers who
demystify consciousness.</i> <i> I meet philosopher of physics,
David Wallace.</i> Some of the smartest people
I know and some pretty good friends take these
approaches very seriously. I find it very difficult
to take it seriously at all. It seems that we don't think we
need a fundamental physics of digestion or a fundamental
physics of respiration even though these are difficult
biological processes that we're really lacking
in [unintelligible]. Consciousness people
seem to think is different, and the reasons they think it's
different I think are intuitions and hunches which can feel very
plausible but when you really interrogate them
are hard to sustain. Well, I think you're still left
with the primary problem, which is the phenomenology
of what we feel and see being a step function different from everything else
we know in the universe. We have a really deep intuition
that these are radically different,
and I share that intuition. What I don't think we have is anything that goes
beyond that intuition. We don't have an argument. We don't have a deduction
that says, these are not the same things. And attempts to get it just mean
more intuitions come up, and I just don't think
intuitions are a great route to truth in science. Lots of things are
really counterintuitive. It's really, really
counterintuitive that your pain literally is a whole bunch of
electrical structural functional goings-on in the brain, but the
fact that it's counterintuitive doesn't make it false. So, what - the conclusion
of what you would say is, is that we live in a universe
where it is possible for electrical activities
to literally be the feeling of consciousness. I don't think we live in a
universe where it's possible, I think we live in a universe
where it's actual. [♪♪♪] KUHN:<i> David's robust physicalism
provides philosophical support</i> <i> for neuroscience's claim
that it can</i> <i> and ultimately will explain
consciousness.</i> <i>That the electrical activity of
the brain just is consciousness.</i> <i> It's called identity theory,</i> <i> and though it feels
counterintuitive,</i> <i> it's just how the world works.</i> <i> In fact, any sort of theory
of consciousness is,</i> <i> in essence,
a kind of identity theory.</i> <i> Something is consciousness.</i> <i> That's why I resist
the mainstream view</i> <i> that neurons
and neural networks alone</i> <i> are sufficient to account
for consciousness.</i> <i> Here's my intuition:</i> <i>Since I must have some identity,</i> <i> I want my identity entity
to be an exotic one.</i> <i> I've seen candidates,
but there is still another.</i> <i> What many think is
the obvious explanation.</i> That consciousness goes
beyond the physical world. [indistinct conversation] <i> I find a physicist who
may agree, Bernard Carr.</i> So, there's no doubt whatsoever
that our experience of the world is affected by the brain. And most people would assume
that if there was no brain, there would be no consciousness. However, to say that the
consciousness is actually generated by the brain
is a completely extra step which isn't implied by that, and there is a different
view which says that actually consciousness is
in some sense more fundamental, and that the brain is merely
a mechanism through which the consciousness
can observe the universe. The standard view
is the reductionist, sort of materialist view
which says that consciousness is just an epiphenomena
generated by the brain. - An emergent phenomena.
- An emergent phenomena. This is saying, no,
actually, consciousness is more fundamental,
and the brain's role is actually almost to limit
your experience. On the face of it, that might
seem a completely bizarre thing to say, but that at least
is the alternative view. And indeed, it seems to me
that it's almost impossible in principle that anything
physical would be able to explain the experience
of consciousness, because by its very nature, consciousness
is a unitary phenomenon. And I've always found it
very hard to understand how that could be generated
by a physical system. So, how do you do it? The only way I can see this
is by having a picture in which consciousness is a fundamental
element of the universe. [♪♪♪] KUHN:<i> Consciousness is
a fundamental element</i> <i> of the universe would require</i> <i> a radical restructuring
of reality.</i> <i> What could that mean
for human awareness,</i> <i> for the universe itself?</i> <i> But can we ever know?</i> <i> What could constitute
refutation or corroboration?</i> <i> I speak with a polymath
physicist who says</i> <i> he takes consciousness
seriously, Paul Davies.</i> I don't believe, I don't think
many of my colleagues would believe that, say, an atom
is individually conscious and that it's a matter of adding
up a whole lots of little bits of consciousness
to get a lot of it. It's got something to do with
the system and the complexity of the system and the way
it hangs together as a whole, that this system is the brain. There is a particular point of
view which is being put forward by Giulio Tononi that somehow
we can characterize the wholeness of the system,
like a brain, say, in terms of a
particular mathematical quantity which he calls
integrated information. I think everybody would agree
that one of the things that brains do
is process information. We get sense data comes in, and
this information swirls around in the brain and then sometimes
leads to agency or action. But where is the information
processing taking place? No neuron in my brain
is conscious, yet the brain as a whole
has consciousness. How do we capture that notion
of the whole being greater
than the sum of the parts? Well, Tononi has
a candidate measurement, and I'm very much drawn to that,
because for the first time, we've got a mathematical
quantity which is defined
on the whole system which captures the two aspects,
one is its complexity but the other is its inability
to be decomposed into the parts without losing the essential
thing that you're looking for. And I'd like to import
that particular quantity into quantum physics
to tackle the measurement and observer problem
of quantum physics. That I can follow. Where I have difficulty was
is going to the next step and saying that
that is consciousness, because it gets back to the old
so-called identity theory, because whatever
that structure is, how does that create
the phenomenal experience? Right.
And that's entirely justified, because what this is,
is a quantitative measure of the degree of consciousness, but it doesn't, in my view,
address what you're describing, which David Chalmers calls the
hard problem of consciousness, these so-called qualia which attach to these
conscious experiences as something which
is outside of the scope of what I've just been saying. And that remains a mystery. What's the implication of that? Does that mean that your
so-called substance dualist is some other thing
that exists in reality that has to somehow work
with the physical world? I think there is something else
that exists, yes. Where I would part company
with some people is to suppose that this other thing could have
an independent existence, floating around
sort of free of the system in which it's instantiated. But I think to fully explain the
world as we experience it, which includes the qualia,
then there has to be something in addition to the particles
and the forces, yes. [♪♪♪] KUHN:<i>
Here's the first big question
in explaining consciousness:</i> <i> Can a complete
and final neuroscience</i> <i> and ultimate understanding
of how the brain works</i> <i> account for the phenomenology
of felt experience?</i> <i> If yes, full stop,
no more questions.</i> <i> If no, go on,
many more questions.</i> <i> Here are three
current contenders</i> <i> for explaining consciousness.</i> <i> One,
integrated information theory.</i> <i> Consciousness is real,
structured, informational,</i> <i> integrated, and exclusive.</i> <i> Consciousness is literally
a succession of unique shapes</i> <i> existing in their own special
dimension or qualia space.</i> <i> Two, consciousness
is a fundamental,</i> <i> irreducible part
of physical reality.</i> <i> It's the bedrock of reality.</i> <i> If so, could there be
deep connections</i> <i> between consciousness
and quantum physics</i> <i> because of the special need
for observers?</i> <i> Or because physics
structures consciousness</i> <i> and consciousness
actualizes physics?</i> <i> Three, consciousness
transcends the physical world.</i> <i> Most scientists despise
a nonphysical explanation,</i> <i> but to explain consciousness,
I cannot reject it.</i> <i> Perhaps only consciousness
takes us Closest to Truth.</i> ANNOUNCER:<i>
For complete interviews
and for further information,</i> <i>please visit closertotruth.com.</i> [♪♪♪]
