June 30, 2025 • 47 mins
Can we explain consciousness as emerging from classical neuroscience, or do we require deeper principles? Could quantum physics have something to do with it? Is it possible that consciousness predates biology, and biology evolved to take advantage of it? What are the right ways to build new theories in neuroscience when we don’t know the answers? Join Eagleman with Nobel laureate Roger Penrose and anesthesiologist Stuart Hameroff to explore the controversial idea that there could be, even possibly, any connection between quantum theory and our awareness of the world.
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Episode Transcript
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Speaker 1 (00:05):
Why do we have the experience of being conscious? Can
you build consciousness just by putting together lots of neurons
in the right way, or might there be deeper principles
at work. Could quantum physics have something to do with
the brain and specifically with consciousness. Is it possible that
(00:25):
consciousness is actually something that predates biology and there's a
sense in which biology evolved to take.
Speaker 2 (00:33):
Advantage of it.
Speaker 1 (00:34):
And what are the right ways to make new theories
in neuroscience when we don't know the answers.
Speaker 2 (00:42):
Welcome to Inner Cosmos with me David Eagelman.
Speaker 1 (00:45):
I'm a neuroscientist and author at Stanford and in these
episodes we sail deeply into our three pound universe to
uncover some of the most surprising aspects of our lives.
(01:12):
Today's episode is about consciousness and quantum mechanics and the
question of whether there could be even possibly.
Speaker 2 (01:21):
Any connection between them.
Speaker 1 (01:23):
So to get at this, I'll be talking today with
Roger Penrose, mathematical physicist and polymath and winner of the
twenty twenty Nobel Prize in Physics, and also Stuart Hammeroff,
an anesthesiologist who has collaborated with Penrose for many years
on a theory. Before we dive into those interviews, I
want to set the table by saying that what we're
(01:44):
going to talk about today are speculative ideas, and many
neuroscientists don't even like to go near them.
Speaker 2 (01:50):
But the fact is that despite the thousands.
Speaker 1 (01:53):
Of neuroscience journals and textbooks and laboratories, there are still fundamental,
basic questions that we don't know the answer to. And
one of the most fundamental is the question of consciousness.
Why does anything feel like something? In other words, imagine
that you built a little toy out of pulleys and
(02:14):
levers and switches.
Speaker 2 (02:15):
Would you say that it is conscious?
Speaker 1 (02:18):
Presumably you wouldn't now double your little toy in size
with new levers and switches and pulleys. Is it conscious?
Speaker 2 (02:26):
Now?
Speaker 1 (02:26):
There's no particular it's theoretical reason to think. So now
keep adding to it. Put on another pulley, in another lever,
and another little door, and attach a wheel, and keep
doing this until you fill a room and then a stadium.
Do you have any reason to assume that it becomes
conscious and has internal experience just because it's more and
(02:48):
more complex. If you now remove a pulley, does it
feel pain. And if you put a little molecular detector
on it such that it can recognize molecules of different
shit apes, does it have a different experience like displeasure
for some shapes and pleasure for other shapes, And where
(03:09):
is that happening. I certainly wouldn't think that your giant
toy is conscious, or at least let me say that,
I have no theoretical reason to believe that it suddenly
experiences pain or hunger or longing or pleasure, because it's
just pieces and parts. So this is a fundamental question
(03:30):
about the brain. We look at your eighty six billion neurons,
which are generally thought of, especially now in this era
of AI, as being units that are popping either on
or off one or zero. And so it's not clear
to any of us in neuroscience why we have private
subjective experience. And this is true whether you have eighty
(03:51):
six neurons or eighty six billion or eighty six gajillion
of them. Why do these little electrical signals and chemical
releases give us the the experience of eating a lemon,
or the pleasure of an orgasm, or the pain of
stubbing your toe. Now, we don't know the answer. But
(04:12):
here's a speculation that some people have put forward. Could consciousness,
the most intimate, subjective, elusive feature of our existence, have
something to do with quantum physics. Now, this is not
a mainstream idea in neuroscience. You're not going to find
it in the standard textbooks most cognitive scientists, if asked
(04:35):
to explain consciousness, we'll talk about neurons and synapses and
the emergent properties of complex systems. The language will be
biological and electrochemical and computational. But a few scientists have
suggested a hypothesis that there's something deeper going on, something
much stranger, and that's what we're going to explore today.
(04:58):
I'm not presenting an argument that auto mechanics does explain consciousness,
but it's worth understanding why some serious minds are entertaining
the hypothesis. So we'll begin with Roger Penrose, who is
perhaps an unexpected figure in this conversation because he's not
a neuroscientist. He's a mathematical physicist. He's done so many
(05:18):
amazing things in his career. He worked with Stephen Hawking
on black hole singularities, or he might know him for
his geometrical shapes called Penrose tiles. And you certainly know
him because in twenty twenty he won the Nobel Prize
in physics for showing that black holes result naturally from
Einstein's general theory of relativity. And by the way, he's
(05:39):
also the one who mathematically described black holes in detail,
including their singularity where all known laws of nature dissolve.
Speaker 2 (05:48):
But especially in.
Speaker 1 (05:49):
The nineteen eighties and nineties, Roger Penrose turned his attention
toward the brain, not because he wanted to build a
better theory about cognition, but because he had a concern
about out algorithms. Penrose felt that consciousness just can't be
explained by any rule based system. He pointed to an
idea called Girdle's incompleteness theorem, which said, look, there are
(06:13):
mathematical truths that we can see to be true, but
they can't be proven within mathematics. In other words, there
are many systems where we can see things to be true,
but the system itself can't prove them. You need to
somehow step outside of the system. Now, to Penrose, this
was a sign that human understanding operates in a way
(06:35):
that transcends computation. In other words, he said, brains aren't
just computers, and if they're not just computers, then the
mystery of consciousness might demand a different kind of physics.
So he wrote a very interesting book called The Emperor's
New Mind, which asserted that the brain can't just be
(06:57):
a computer. So in your Book's New Mind, which I
read as a young person and really loved, so you
argue that consciousness can't be explained by algorithms.
Speaker 2 (07:10):
So help us to understand that.
Speaker 3 (07:12):
But it really means, you see, an algorithm is just
the sort of technical word for a computer program. I
feel like maybe people use that term. It just means
that you have a rule which is a computational rule.
Speaker 1 (07:25):
Right, And why what made you feel that consciousness can't
be explained by algorithms?
Speaker 3 (07:30):
Well, it goes back to the Girdle the lecture that
Stein gave about Girdles theorem. And I realized that you see,
if you see mathematical proof, you could have a set
of rules, axioms and rules of procedure. These are of
a nature that you could put them on a computer.
Speaker 1 (07:51):
You think there are forms of human insight that fundamentally
cannot be replicated by algorithms.
Speaker 2 (08:00):
Is that that's correct.
Speaker 3 (08:01):
Okay, yes, absolutely right.
Speaker 1 (08:03):
Okay, great, and so and so that made you think
that maybe this mystery of consciousness needed to be taken
seriously by physicists and mathematicians. So, yes, So how did
you how did you start addressing this?
Speaker 3 (08:20):
I was trying to think about the laws of physics
that we sort of understand, and some of them are
very powerful. Well, even you turn in mechanics explains an
awful lot and science general theory of relativity explains a
lot more, and it's more difficult to apply things, but
(08:42):
it's still computational. What about quantum mechanics?
Speaker 1 (08:45):
Now, before we go further, I just want to give
a reminder about what quantum physics is. It's the branch
of physics that describes the behavior of matter and energy
at the smallest possible scales, at the level of atoms
and subatomic particles, and down there the world behaves nothing
like what we're used to. Particles can be in more
(09:07):
than one place at once. This is what's known as superposition.
Particles can become mysteriously linked across space in what's called entanglement.
And the most bizarre feature of all is that the
mere act of measuring a system seems to affect its outcome.
This is what's called the observer effect. In our current
(09:27):
understanding of quantum mechanics, the story is that until a
particle is observed, its properties don't exist in a definite way.
Speaker 2 (09:36):
They exist only in probabilities.
Speaker 1 (09:39):
In other words, a quantum particle doesn't have a precise
location until you look at it. Until that moment, it's
smeared across a range of possibilities, and then those possibilities
collapse to one outcome when you observe. Now, this isn't
just a metaphor. This general idea has been tested and
(09:59):
confirmed for over a century, and it's built into the
fabric of our technology. Quantum mechanics is the science that
allows the transistors in your cell phone, and the lasers
at the grocery store scanners and the GPS in your car.
Quantum mechanics is real, and it's very countereteitive, and it
seems to tell us that at the heart of reality
(10:21):
is a kind of indeterminacy, a fuzziness that only collapses
into certainty when it's observed. So think of it roughly
this way. You toss a coin in the air and
while it's spinning. It's not heads or tails. It's sort
of like it's both at once, but the instant you
catch it and look, it becomes just one heads or tails.
(10:45):
That moment of catching it is like the wave function collapsing.
Speaker 2 (10:48):
Now here's the thing. In quantum mechanics.
Speaker 1 (10:50):
There's no way to predict what the coin's going to be,
heads or tails, and so that non computable strangeness, that's
what Penrose was interested in. He wondered, what if that indeterminacy,
that collapse of possibilities into one real outcome, wasn't just
a physical process but also has to do with a
(11:13):
mental one. In other words, what if the flicker of
consciousness is related in some way to the collapse of
the quantum wave function. So back to Penrose talking about
(11:41):
his search for something non computable and getting interested in
the collapse.
Speaker 3 (11:46):
What about quantum mechanics? Then I thought, wow, I was
shruding no equation, that has no problem about putting that
on there. Maybe lots of parameters involved, it's make it tricky. Well,
that's a well determined determined It is a good question.
Roading equation doesn't give you what happens in the world.
Why doesn't it give you what happens. Schrodering himself was
very keen on explaining these things and his well known cat.
(12:11):
He was making this is an absurdity. To have a
cat which is dead and alive at the same time
is a nonsense. This is point of what he was
trying to make. He was saying, this is an absurdity.
His equation he was trying to say. He was saying,
roughly speaking, my equation does not describe reality. There is
(12:32):
something more. And this something more is what we tend
to call the collapse of the wave function. You're a
wave function drugs along and behaves according to the Schroding
equation very reliably and honestly, and then from now time
to time it says, whoops, I'm going to do something else,
and then it becomes probabilistic, and it's all hidden in
(12:54):
all sorts of man and manical schemes.
Speaker 1 (12:58):
So you mean is that classical computation can't explain consciousness,
and so the question is then what can? And this
is where you make the fascinating proposal that quantum mechanics,
and specifically the collapse of the wave function, might be
involved in consciousness.
Speaker 3 (13:17):
See people say sometimes I'm just not say, well, here's
the problem, and here's a problem. So they're the same thing.
It's not that it's that we need something which is
not a computable part of physics. What is it in
the physics that we know it would not be possible
to put on a computer. Well, you see, if the
collapse of the wave function is purely random, then you
(13:38):
could put it on a computer source off. And it's
not perhaps really random, it's something very subtle, and you
need that for the collapse of the wave function. And
the story has developed in other ways beyond what I had.
Then you see, this was the beginning of the story,
and you're asking me about the beginning. The beginning was
the story. It was a little bit in the sense
(14:00):
that I didn't know really much about what to do.
I could see that in according to my new point,
the collapse of the wave function had to be a
major part of the physics which is responsible for evoking consciousness.
Speaker 1 (14:18):
So to summarize where we are, Roger felt certain that
consciousness couldn't be explained just by classical computation. Again, most
of quantum mechanics you can easily model on a computer,
like the evolution of the Schrodinger wave function, but there's
something very weird about the collapse. That's the part you
can't compute. So Roger felt he was onto something interesting there.
(14:41):
So he sat down and wrote The Emperor's New Mind,
and the title, as you might guess, was a reference
to the story of the Emperor's New Clothes. The idea
being that everyone is assuming we can explain consciousness by
putting together enough neurons, but in fact, in his view,
the burr is naked consciousness possibly can't be explained by
(15:04):
just a bunch of neurons. So I asked Roger what
happened just after he published the book In nineteen eighty nine,
I wrote.
Speaker 3 (15:11):
My book Them Prisoner Mind and hoping some young people
might be stimulating, and only got old retired people. I
thought I'd done lo It was sort of a fairly
reasonable job as an ignoramus, but not too bad at
a job of trying to learn the main features of neurophysiology.
Speaker 1 (15:27):
So Roger started studying up on the brain, really as
a side gig to his mathematical physics career. But the
more he looked at it, he thought that maybe the
macro level at which we were able to study.
Speaker 2 (15:38):
The brain wasn't really revealing its secrets.
Speaker 3 (15:41):
And I would say that it has a genuine, deep purpose,
and that purpose is not clearly revealed in the structures.
But it's not something which is obviously like a computer.
Something else going on. But I didn't know what was
going on. I had no real idea by the time
I got to the end of my own presuming but
(16:02):
I just I might. I could have stopped writing in
this point, and I said, well, that's I've written so
much so far.
Speaker 2 (16:07):
I better go on.
Speaker 3 (16:09):
And so I'm more or less sort of some idea
which I didn't really believe. I tried to think of
something that might be non computable, you see.
Speaker 2 (16:16):
So that's where things were for Rogers' idea.
Speaker 1 (16:19):
He suspected there must be some kind of quantum effects
in the brain, but he didn't know where to look.
But at the same time, in America, there was a
young antesthesiologist named Stuart Hammeroff who was interested in consciousness.
Speaker 4 (16:32):
And I got interested in consciousness, and I went to
med school and was interested in neurology, neurosurgery, psychiatry. But
I didn't like those lifestyles, particularly what they got to do.
They didn't actually get to do the surgency, but the
neurologists in particularly didn't have much to do. And I
took a research elective over summer in a cancer lab
(16:53):
and studied my toasters. I figured just try something different,
and so we uh studying cell division. And as you know,
the cell divide, the chromosomes are separated by these spindles,
which are microtubules.
Speaker 2 (17:04):
That's Stuart hammer Off.
Speaker 1 (17:05):
And while everyone in that lab was interested in the chromosomes,
where the genes are, he found himself interested in the microtubules. Now,
what are microtubules. The starting point here is that all
the cells in the brain, like neurons and glial cells,
are not empty. Inside every single brain cell is a
bustling inner world. You've got all kinds of structures that
(17:27):
help the cell keep its shape and transport materials around.
And among these structures are microtubules, which are tiny hollow tubes.
They're part of the cells skeleton. Sometimes people think of
these like the tracks that guide packages through a warehouse.
Now these are very very tiny. Each microtubule is about
(17:48):
twenty five nanometers in diameter, which means you can line
up four thousand of them across the width of a
single human hair, and they're long too, so they stretch
like tiny straws all through the interior of the neuron.
Now what's amazing is these are constantly assembling and disassembling themselves,
almost like living legos, and this adjusts the internal architecture
(18:11):
of the cell in real time. So Stuart got interested
in these microtubules and wondered if they were more than
just railroad tracks.
Speaker 2 (18:20):
Back to Stuart Well.
Speaker 4 (18:21):
Micro teams are found in all cells, including neurons, which
are full of them, and they are like the skeleton
and the scaffolding on the cell, but they're also the
nervous system of the cell. They organize things, and their
structure I learned back then is a lattice kind of
like a computer lattice, where you have individual units proteins
called turbulence that I thought back then can be in
(18:43):
two states, like flexing like a peanut open and closed,
and that would be like a bit at one or zero.
Speaker 1 (18:49):
So Hammerff is looking carefully at these and he proposed
that microtubules might be doing something beyond structural work, that
instead of just looking at the microtubule as a roadway,
you might think about the details of the microtubules and
ask whether this could be a structure that was a
lot more interesting than it first appeared. So he started
(19:11):
modeling tubulens, the little bricks of microtubules, and came to
the conclusion that you could store something like ten to
the sixteenth bits of information in a single neuron using microtubules.
And this was essentially the number that people were talking
about for the storage capacity of the entire brain.
Speaker 2 (19:29):
Now, his colleagues were skeptical. They didn't want to hear it.
Tell me to get lost.
Speaker 4 (19:32):
So except then one day, fateful day, this guy said
to me, Okay, why is that asked? Let's say you're right,
how would that explain consciousness? How would that explain love, feelings, pinkness, joy,
blah blah blah. Essentially the hard problem five years before
Dave announces. But you knew the problem, I said, WHOA,
you're right, I have no idea. I was a reductionist nudgeon,
(19:55):
and I was ashamed of myself.
Speaker 1 (19:56):
Actually, so we actually just want to say, I want
to make sure everyone's following. So the hard problem of
consciousness is you've got all this physical stuff happening in
the brain, why does it feel like anything.
Speaker 2 (20:05):
Why do we have experience? That's the hard problem.
Speaker 1 (20:07):
Okay, Right, so you were looking at these microtubules which
are made up of these tubulin peanut shaped proteins, and
you're saying, hey, there's something really interesting here. But it
didn't solve the hard problem.
Speaker 2 (20:18):
Right.
Speaker 4 (20:19):
So I was just saying, more computation, more information processing.
So and the guy had a beautiful point, and I
was kind of stunned. And he said, you should read
this book by Roger Penrose called The Emperor's New Mind.
I said, I've kind of heard of that guy. So
I bought the book. I read it, and I was
kind of blown away. I mean, it's an amazing book.
The first half is about why consciousness is not a computation.
(20:41):
He used something called Girdle's theorem from mathematics, which said
a mathematical theorem cannot prove itself. You need somebody or
something outside the system, like a mathematician, to say yeah,
it's true or not. And he extrapolated and said it's
like understanding, you know, to understand something, you need to
be outside the system, very similar to John Searle's Chinese
room argument. You know, the guy has the Chinese symbols.
(21:02):
He looks them up and he translates, but he doesn't
understand Chinese.
Speaker 2 (21:05):
So that's the sense just doing computer operations, right.
Speaker 4 (21:08):
And so that was the difference and Roger. So the
second half of the book was Roger's solution, which had
something to do with quantum physics and collapse of the
wave function, the measurement problem in quantum Kinnis, which was
a whole other mystery. But he said, the solution to
that mystery is the same as is for consciousness. But
Roger didn't have a biological structure that could be at
(21:29):
the quantum level. And he said in the book, I
don't know what it is. Maybe somebody does. So I
read the book and I said, holy crap, he needs microtubules.
I've been studying for twenty years.
Speaker 2 (21:37):
So Stuart wrote Roger a letter.
Speaker 3 (21:40):
But then Stuart Haerrov read my book and wrote back
to me said, evidently you don't know about microtubules. He
was absolutely right. If I'd known about microtubules, that's it.
Here's a much better bet. For various reasons, they are
probably because they're too See. It seemed to me that
(22:02):
there is a much better chance you could isolate quantum effection.
Speaker 1 (22:06):
So they met up in England and Roger was very
taken by the geometry of these microtubules. Tell us what
is special about microtubules?
Speaker 3 (22:16):
Well, what's special about microtubules? There's several things which excited
me about them. Some of them are sort of peripheral,
but not so stupid. Maybe they are two to begin with,
and that struck me as much better chance preserve coherence.
You see, if you're going to have the collapse of
the wave function, you've got to have a well defined
(22:37):
wave function which isn't collapsed by the environment. You see,
normally what happens is that the environment collapses that and
that's no use to anybody this standard, As I say,
Ladi von Neumann arguments, do you say that the collapse
occurs because the environment gets involved? You have no control
over the environment and so therefore it behaves randomly in someone.
Speaker 1 (23:00):
In other words, he's pointing out that the environment normally
collapses the wave function very rapidly. But he appreciated the
possibility that microtubules might serve as a wave guide, which
means there's something about the particular structure of these long,
thin straws that keeps the wave function uncollapsed for a
longer time. A.
Speaker 3 (23:21):
Their tubes. B. They have a very symmetrical structure of
the tubulence, and they combined together in this particular structure,
which I found fascinating because it has, for example, symmetries
in three different directions. One is along the axis, one
(23:43):
is twisting one way, and the other is twisting the
other way. So it just struck me what's funny about
these microtubules. You have these microtubules which have one direction
along the tube, and that seems mirror what you get
in these tubes, that they become super conductive. So this
(24:03):
suggested to me that maybe there is some quantum super
conductive effect along the tubes, which is quite different from
nerve transmission, which is absolutely a quantum effect.
Speaker 2 (24:18):
So the idea is you've.
Speaker 1 (24:18):
Got these microtubules which are inside all the neurons and
these conservative waves guides. One of the criticisms that people
have had about quantum mechanics in the brain is they say, look,
it's too warm and noisy in there.
Speaker 2 (24:34):
What do you say in response to that.
Speaker 3 (24:38):
Well, that's a general comment you might expect that applies
if it hasn't gone some very very specific structure, and
the market tube was I thought, much better chance of
that sort of thing. I mean, they're doing a pretty trick,
pretty good trick, you see. If they actually are preserving
coherence along the tubes, this is a neat trick that
(25:00):
nature allegedly. I'm saying that to say that's my viewpoint,
must actually have succeeded and making this trick. I'm The
general comment is warm and messy, sure as a whole,
but there are structures when this warm and messy thing.
You don't need the whole thing to be structured in
this way. You just need certain elements in this complicated structure,
(25:24):
which as a whole may be warm and messy and
all sorts of things. But there are things, the claim goes,
which can preserve quantum coherence. And the idea is that
maybe microtubules do. And when I heard about them from Stuart,
I thought that was a much better case than anything
I'd seen before.
Speaker 1 (25:40):
So hammer Off and Penrose got interested in this possible
relationship between microtubules and quantum mechanics. But what does any
of this have to do with consciousness? Back to my
interview with Stewart in quantum Mechanics, things can be in
different positions. The wave function predicts how that moves along nicely.
But what happened as you get a collapse of the
(26:01):
wave function, which tells you, hey, let's say the particle
is over here, over here, and the idea was the
collapse that moment when that happened, there's some consciousness in
the universe.
Speaker 2 (26:14):
That's what he predicted. That's what he predicted.
Speaker 4 (26:16):
People are saying conscious comes to the outside and causes
the collapse, but that puts consciousness outside science. It's a
dualist position. And actually one of the charmers takes now,
but it goes back to Vignaer and von Norman and
Boord early part of the twentieth century and then and
others had didn't want collapse to deal with it or consciousness,
(26:36):
so they just said many worlds, it's easier to think
about the consciousness. And Roger came up with a solution, says,
the separations are unstable and will collapse and give consciousness
and due to an objective threshold given by the indeterminacy
principle one equation.
Speaker 1 (26:53):
Okay, and so who is experiencing the consciousness or the
quality of when there's a collapse of the wave function.
Speaker 4 (27:00):
The collapse itself is who's is who, what is experiencing.
I don't think it is controversial. I don't think there
needs to be a separate self. Other people disagree with
me on that, but I think if you have a
sequence of experiences and memory, you have a self. You
know who you are, you know when you wake up
the morning, the same person moment to moment. So I
(27:21):
don't think there's any separate entity as the self. I
think just I think you have a sequence of experiences,
complex experiences. I should go back and say when, when
when the objective reduction that's his name for objector threshold,
quantum state reduction, objector reduction, or or when that occurs
in the environment and in the chair anywhere other than
(27:45):
in particular arrangements. It's the experience is random, fleeting, disconnected.
It comes and it goes. It's apparently happening all around us.
We never noticed. It's like and that was proto conscious,
so that they call that proto conscious, and I liken
that too. If you go to the symphony and the
musicians are tuning their instruments before and you hear all
(28:06):
this to me noise to train the musicians different. But
to me, it's like uh uh, you know, it's it's
noise and then they start to play and it's Broms
or Beethoven or whatever, and uh. And that's what the
brain does, that's what the micro tubuas do. Orchestrates the
objective reduction. Hence the theory is orchestrated objective reduction.
Speaker 1 (28:26):
Okay, so when there's the collapse of the wave function,
there's a little bit of consciousness. But if you build
a device in the right way where you've got all
these microtubules that are guiding this, that are orchestrating this
whole thing, then you get something like our contry and
they have to they.
Speaker 2 (28:42):
Have to be entangled.
Speaker 4 (28:43):
So the superposition states become part of one one much
more complicated state. So when you when we're collapsing our
conscious moments, now there's a lot of richness in it.
I see you, you see me, I see this stuff
behind you, et cetera, et cetera. And so and there's sound,
there's different senses. It's all orchestrated. I would say integrated,
but that's a different theory. It's more orchestrated.
Speaker 1 (29:05):
Now, what would that get us to have entanglement across
different regions of the brain. Well, one example Stewart turns
to is what's called the binding problem. The binding problem
is a long recognized mystery that different regions of the
brain encode very different types of information like.
Speaker 2 (29:24):
Movement here, and colors here.
Speaker 1 (29:27):
And face recognition and sound and touch, and yet you
enjoy a totally unified experience. For example, let's hey watching
a basketball player race down the court dribbling the ball.
Different areas of your brain are processing the shape and
the movement and the sound of the ball hitting the court,
but you perceive the whole thing as one guy racing
(29:50):
down the court. The colors and the motions and the
sounds don't separate off from one another. So how are
these distinct features processed in total different brain regions integrated
into one seamless perception. This remains a central mystery in neuroscience.
So how might their theory address.
Speaker 4 (30:11):
That spatial temporal binding? You know, you see something moving
through the sky and its shape, color, motion, meaning or
processed at different places at different times in the visual
cortex and cortex in general. And yet we see one object,
we see a yellow kite fluttering instead of yellow kite
fluttering move. We see one thing instantaneously, so it's it's
integrated or orchestrated in time, and also in different regions
(30:36):
of the brain. So I think the brain needs entanglement
one way or the other.
Speaker 1 (30:39):
So, in other words, neuroscience traditionally just thinks about neurons,
and those are in some sense quite slow.
Speaker 2 (30:46):
But maybe Hammers.
Speaker 1 (30:48):
Suggests there are much faster processes. They're binding things together.
Speaker 4 (30:53):
It's more like music. It's more like resonance harmonics, interference beats.
In fact, to get from the very fast and very
slow interference beat, it's probably what does it. So I
think the brain is more a quantum orchestra than a computer.
Speaker 2 (31:06):
Got it.
Speaker 1 (31:07):
And so essentially all our technologies are just measuring what
neurons are doing. Like you dunk electrode in and you
see the spike head of the neuron.
Speaker 4 (31:14):
And so they're only listening to the base and percussion
of the symphony. They're missing the flutes and the piccolos
and everything else. And what makes you think this The
other theories don't work. All the other theories are based
on a neuron firing is a bit or a neuron
is essentially a one or a zero. And if you
look at a single cell organism like a paramesium, it
(31:37):
swims around, It finds food, it finds the mate, it
has sex, it can learn. If you suck it into
a capillary tube, it gets out faster and faster each
It's one cell, and it does all that with its microtubules,
whether it's silly and it's internal microtubules. So if a
paramesium can do that, and are you serious and thinking
that a neuron is a one or a zero and
that's it, it's an insult in neurons.
Speaker 1 (32:15):
So together, Penrose and Hammeroff worked on their idea of
entanglement going on.
Speaker 2 (32:19):
Across the brain.
Speaker 1 (32:21):
And the hypothesis is that these deep tubes humming away
deep inside the brain's machinery, these orchestrate when and what collapses.
So they call this orchestrated objective reduction. Give me the
idea of orchestrated objective reduction?
Speaker 2 (32:39):
What does that.
Speaker 1 (32:40):
Mean and how does that explain consciousness potentially?
Speaker 3 (32:44):
Okay, think of as I used to play ping pong
when I was at school, for instance. You see, as
I never achieved any great skill with this, but I
can understand there's just a game where you have to
act very quickly, and the way if I flick the
ball into the right hand corner as opposed to the
(33:06):
left hand corner, it's because I think by looking at
my opponent that he's not expecting it for me to
flick it into the left hand corner, and so I
do that flick into that corner because I think from
what I've just gained it's very small fraction of a second,
much less than half a second. I estimated that this
(33:26):
is a good thing to do, so I think that
was a conscious choice. Now, what is the current view
amongst I believe, and I get this from Stewart. The
current view amongst neurophysiologists is that these actions are not conscious,
they're much too quick. But Stewart's view and mine is
it is conscious, but it can only occur because of
(33:51):
the following mechanism. The argument would be that you could
preserve quantum coherence at a big level that is sufficiently
isolated from the outside world that in this layer you
could preserve a lot of quantum coherence, so that this
would mean that the action of flicking the ball this
(34:12):
way rather than that way, and this choice is it
made conscious consciously. The current view is there's no time,
that the consciousness come about, much too late for this.
But our view is no, there is time because the
choice of which action to take can be a conscious one.
(34:34):
The action taking involves a lot of nerve transmissions and
making your this way rather than that way, and all
these things. I think of a tennis player deciding to
go cross court rather than the bat down the line,
and that involves different muscle muscle actions. Now those different
muscle actions can be in superposition, kept in superposition, so
(34:58):
which one of them is truck It can be done
very quickly and those then the actions take place and
the person that's what has decided to be done. So
although the conscious action to move all those particular muscles
like this, and that's not conscious, what's consciousness. I'm going
to flick the ball to the right rather to the left.
(35:21):
And so that is a whole lot of different motions
which are all together in superposition. So this is the
idea that this collection of motions and that collection's motions
and which ones are activated are all there together, and
which one is activated is a conscious choice. And that
conscious choice, as it is at a quantum level choice
(35:44):
in these very specific cells that you get the coherent
superposition of different actions. So it could be this it's
under control all this one or this one, and they're
all there in quantum superposiniess. So the choice you make
as to which one is controlled is a quantum choice.
Speaker 1 (36:05):
And presumably when when the waveform collapses, that's when you
become conscious of something.
Speaker 2 (36:12):
That's that's the idea. Yes, that's what it is.
Speaker 3 (36:15):
Consciousness is to do with the actual collapse.
Speaker 1 (36:18):
One intriguing thing is that this proposal seems to blur
the line between physics and philosophy in an interesting way. So,
if consciousness arises through quantum processes, does that suggest that
consciousness is not just a feature of brains, but a
more fundamental property of the universe.
Speaker 2 (36:41):
How do you see this?
Speaker 3 (36:42):
Yes, but you see, But it might be you've got
to get it organized in a very subtle way in
order to reveal. You see, the collapse part of it
might be easy to reveal, but the way in which
it's not quite random and quite random, probably in a
very sophisticated way.
Speaker 1 (37:01):
Does this hypothesis have implications for free will?
Speaker 2 (37:08):
That's a very good question.
Speaker 3 (37:10):
You see, I'm even quite recently sort of changed my
view on this question. I often thought it's a sort
of meaningless question in a way. I mean, does it
mean that a quantum effect is brought into play because
quantum thing is not deterministic? And does the fact that
it's not deterministic mean free will? Not normally because it's random?
(37:32):
And if it's random, that's not free will. I mean
you're just tossing a toy. It's not random because it's
got to be doing something. I mean, randomness isn't beneficial.
Speaker 2 (37:43):
In a way.
Speaker 3 (37:44):
You see, you could make it random, but that's not
the point free will. You could say that, you see,
people often say that free will could be there if
it's not deterministic, but it doesn't know you any good
if it's just right. So the view I have is
more or less this. It's not even money. It's a
(38:06):
very recent view, I think. But the view is more this.
There is something rtrachursal about it. What free will really
means and what I'm arguing for here. It's not that
you can do anything you like, and you can act
randomly if you like. You're doing what you think is
the right thing to do, so you have the free
(38:27):
will to do what you think is the right thing
to do, and it doesn't necessarily be righteousness center virtuous.
It means, in your judgment, the correct thing to do.
Whether it's correct, desper for or beneficial less or for
the goodest, the whole, or whatever, that's not the point.
The point is that you are doing it because you
(38:47):
think it's the right thing to do. Now that means
you're understanding it.
Speaker 1 (38:53):
What kind of experimental result would excite you most in
the coming years.
Speaker 3 (39:00):
I think if you're looking at things plausible within current technology,
maybe some convincing kind of quantum coherence within microtubules.
Speaker 2 (39:09):
I want to ask you about AI.
Speaker 1 (39:11):
We've seen such incredible progress in classical AI systems, but
given your view that consciousness involves non computable processes, do
you think that AI is conscious, could be conscious or
is it just an impressive simulation.
Speaker 3 (39:31):
No, in one word, it's not conscious, and it's not
going to be conscious by having more and more and
more elements in your computers.
Speaker 1 (39:42):
So could a quantum computer in the future. Could a
quantum computer be conscious if it were designed with the
right architecture or is something else still missing?
Speaker 3 (39:50):
You have to be careful about what you mean by
a quantum computer, because I don't think quantum computer in
the sense that people use that term does actively role
using the collapse of the wave function as part of
the mechanism in quotes, because it's not really a mechanism.
Speaker 2 (40:07):
That's right, Yeah, okay, got it.
Speaker 1 (40:09):
So the kind of quantum computers that for example, Google
is working on now, because presumably it doesn't involve the
collapse of the wave function, you think it wouldn't be
conscious as such.
Speaker 2 (40:22):
Yes, that's right, Okay, great.
Speaker 1 (40:24):
I asked Stuart the same question about whether contemporary AI
could be conscious.
Speaker 4 (40:30):
Not with the kind of computers we am now, not
with a silicon based And you know, our friend Dave Chalmer's,
after decades of the heart problem, recently came out and said,
well AI consciousness is inevitable and throwing the heart problem
under the bus.
Speaker 2 (40:46):
Totally interesting, and then backing up and.
Speaker 4 (40:50):
When I questioned him about it, he said, well, what's
the fundament there's no fundamental difference between silicon and carbon.
Speaker 2 (40:56):
I said, wrong answer today. First of all, it's not carbon.
Speaker 4 (40:59):
It's organic carbon, which means aromatic rings, which means quantum.
So that and there's a huge difference between organic carbon
and silicon. Silicon can't do that. So and this organic
carbon aromatic hydrocarbons have been in the universe right from
the start.
Speaker 2 (41:17):
So let's summarize.
Speaker 1 (41:19):
According to this idea from Penrose and hammer Off, the
brain isn't just a network of firing neurons. It's also
a kind of quantum computer. Inside every single brain cell
is a whole world of microtubules, these tiny cylindrical structures
that are so small they've traditionally been ignored. But maybe
(41:40):
they suggest these structures are doing more than organizing the
cell's interior. Maybe these microtubules are hosting quantum processes. Maybe
they're sustaining delicate quantum states long enough to do something
meaningful and entangling across cells, and that the collapse of
(42:00):
these states might correspond to moments of conscious experience. Now,
I just want to repeat one point. You might be thinking, Wait,
doesn't quantum physics get washed out in warm, wet environments
like the brain. That's a reasonable objection. In fact, it's
one of the main reasons that many scientists have been
skeptical of the orchestrated objective reduction theory. Quantum coherence usually
(42:25):
does not last long in messy biological environments.
Speaker 2 (42:28):
It's fragile.
Speaker 1 (42:30):
But on the other hand, that skepticism has been challenged
in recent years by findings in other parts of biology.
Quantum effects have now been observed in photosynthesis, in bird navigation,
in the sense of smell. Somehow, living systems might be
more hospitable to quantum phenomenon than we thought. And if
(42:51):
that's the case, then maybe, just maybe, the brain has
found a way to leverage quantum effects, not just for computation,
for consciousness itself. Now, Penrose and Hamros's theory and others
like it remain highly speculative. Neuroscience continues to make great
progress without invoking quantum mechanics artificial neural networks, which are
(43:14):
entirely classical in their architecture. These have achieved unbelievable feats
like the modern blossoming of AI. But so far as
we know, artificial neural networks like CHATCHPT are not conscious,
and so the idea here is that we need to
think not just bigger, but perhaps also sub microscopically smaller.
(43:36):
So we've just heard from two thinkers who aren't afraid
to step beyond the comfortable borders of their fields. To
probe around in areas that most scientists won't touch. What
I find so compelling isn't the certainty of the theory.
It's the audacity of the question. It's the willingness to say, look,
perhaps our current tools aren't enough. Maybe consciousness isn't just
(43:59):
a clever computation, but something much stranger. Maybe the deepest
puzzles in neuroscience can't be solved without rethinking everything from
the ground up. There's a long history of big leaps
in science, beginning with questions that sounded naive or mystical.
There was a time when most of the ideas we
(44:20):
take for granted today were ridiculous. So I want to
return to one last thought from Roger. What advice would
you give to young scientists who are drawn to the big,
risky questions about consciousness but are afraid to step too
far outside conventional boundaries.
Speaker 3 (44:37):
To try and do the following. You will have some
specialist view that you see in order to make progress,
you have to dig deeply in a certain area and
understand that area as well as you can and better
than most other people. But you also, at the same
time should keep a broad outlook of what's going on
in the outside world and pick up maybe if you
(45:01):
see something which might connect with what you're doing.
Speaker 1 (45:03):
There are plenty of critics of this idea who point
out reasonably that there's not enough experimental evidence to take
this idea with the requisite seriousness yet. But it's okay
to explore the speculative as long as we keep one
foot planted in the empirical. It's a key to making
progress in science is balancing skepticism with curiosity and openness.
(45:26):
All of us in neuroscience like to believe that we're
close to cracking the puzzle of consciousness, but the fact
is we're probably just at the foot of the mountain,
and it's always possible, just like in any field, that
we're not even asking the right questions.
Speaker 2 (45:40):
Yet.
Speaker 1 (45:41):
What if we've been looking at the hardware in an
incomplete way and missing the best tricks of physics. The
fact is that the central mystery of neuroscience, for which
no one has a good answer, is the hard problem
of consciousness. Why if we have an organ that goes
around and collects information than a camera or a microphone,
(46:02):
why does it feel like something, presumably in a way
that your iPhone does not When it makes recording. Why
do we have private, subjective experience of the world. Quantum
mechanics may or may not provide the answer. Maybe we're
all just shooting in the dark until we discover a
new field and one hundred years from now called Schwanton mechanics.
(46:23):
But whatever the case turns out to be, it seems
likely to me that the neuroscience textbooks used by our
great great grandchildren will have very different stories than we
do today, and future centuries will look back on our
scientific frameworks with the quaintness that we look back on
ideas of flagiston or spontaneous generation, or that the Earth
(46:48):
was at the center of the universe.
Speaker 2 (46:50):
But the only way we're going to.
Speaker 1 (46:52):
Get there is to keep digging deeper and asking, by
not falling for the assumption that we've got it all
figured out with our stand in textbook models, but by
continuing to propose and put to the test brave new hypotheses.
(47:13):
Go to Eagleman dot com slash podcast for more information
and to find further reading.
Speaker 2 (47:18):
Check out my newsletter on substack and be a part
of the online chats there.
Speaker 1 (47:23):
You can watch the videos of Inner Cosmos on YouTube,
where you can leave.
Speaker 2 (47:26):
Comments until next time.
Speaker 1 (47:29):
I'm David Eagleman and this is inner Cosmos.
Why do we have the experience of being conscious? Can
you build consciousness just by putting together lots of neurons
in the right way, or might there be deeper principles
at work. Could quantum physics have something to do with
the brain and specifically with consciousness. Is it possible that
(00:25):
consciousness is actually something that predates biology and there's a
sense in which biology evolved to take.
Speaker 2 (00:33):
Advantage of it.
Speaker 1 (00:34):
And what are the right ways to make new theories
in neuroscience when we don't know the answers.
Speaker 2 (00:42):
Welcome to Inner Cosmos with me David Eagelman.
Speaker 1 (00:45):
I'm a neuroscientist and author at Stanford and in these
episodes we sail deeply into our three pound universe to
uncover some of the most surprising aspects of our lives.
(01:12):
Today's episode is about consciousness and quantum mechanics and the
question of whether there could be even possibly.
Speaker 2 (01:21):
Any connection between them.
Speaker 1 (01:23):
So to get at this, I'll be talking today with
Roger Penrose, mathematical physicist and polymath and winner of the
twenty twenty Nobel Prize in Physics, and also Stuart Hammeroff,
an anesthesiologist who has collaborated with Penrose for many years
on a theory. Before we dive into those interviews, I
want to set the table by saying that what we're
(01:44):
going to talk about today are speculative ideas, and many
neuroscientists don't even like to go near them.
Speaker 2 (01:50):
But the fact is that despite the thousands.
Speaker 1 (01:53):
Of neuroscience journals and textbooks and laboratories, there are still fundamental,
basic questions that we don't know the answer to. And
one of the most fundamental is the question of consciousness.
Why does anything feel like something? In other words, imagine
that you built a little toy out of pulleys and
(02:14):
levers and switches.
Speaker 2 (02:15):
Would you say that it is conscious?
Speaker 1 (02:18):
Presumably you wouldn't now double your little toy in size
with new levers and switches and pulleys. Is it conscious?
Speaker 2 (02:26):
Now?
Speaker 1 (02:26):
There's no particular it's theoretical reason to think. So now
keep adding to it. Put on another pulley, in another lever,
and another little door, and attach a wheel, and keep
doing this until you fill a room and then a stadium.
Do you have any reason to assume that it becomes
conscious and has internal experience just because it's more and
(02:48):
more complex. If you now remove a pulley, does it
feel pain. And if you put a little molecular detector
on it such that it can recognize molecules of different
shit apes, does it have a different experience like displeasure
for some shapes and pleasure for other shapes, And where
(03:09):
is that happening. I certainly wouldn't think that your giant
toy is conscious, or at least let me say that,
I have no theoretical reason to believe that it suddenly
experiences pain or hunger or longing or pleasure, because it's
just pieces and parts. So this is a fundamental question
(03:30):
about the brain. We look at your eighty six billion neurons,
which are generally thought of, especially now in this era
of AI, as being units that are popping either on
or off one or zero. And so it's not clear
to any of us in neuroscience why we have private
subjective experience. And this is true whether you have eighty
(03:51):
six neurons or eighty six billion or eighty six gajillion
of them. Why do these little electrical signals and chemical
releases give us the the experience of eating a lemon,
or the pleasure of an orgasm, or the pain of
stubbing your toe. Now, we don't know the answer. But
(04:12):
here's a speculation that some people have put forward. Could consciousness,
the most intimate, subjective, elusive feature of our existence, have
something to do with quantum physics. Now, this is not
a mainstream idea in neuroscience. You're not going to find
it in the standard textbooks most cognitive scientists, if asked
(04:35):
to explain consciousness, we'll talk about neurons and synapses and
the emergent properties of complex systems. The language will be
biological and electrochemical and computational. But a few scientists have
suggested a hypothesis that there's something deeper going on, something
much stranger, and that's what we're going to explore today.
(04:58):
I'm not presenting an argument that auto mechanics does explain consciousness,
but it's worth understanding why some serious minds are entertaining
the hypothesis. So we'll begin with Roger Penrose, who is
perhaps an unexpected figure in this conversation because he's not
a neuroscientist. He's a mathematical physicist. He's done so many
(05:18):
amazing things in his career. He worked with Stephen Hawking
on black hole singularities, or he might know him for
his geometrical shapes called Penrose tiles. And you certainly know
him because in twenty twenty he won the Nobel Prize
in physics for showing that black holes result naturally from
Einstein's general theory of relativity. And by the way, he's
(05:39):
also the one who mathematically described black holes in detail,
including their singularity where all known laws of nature dissolve.
Speaker 2 (05:48):
But especially in.
Speaker 1 (05:49):
The nineteen eighties and nineties, Roger Penrose turned his attention
toward the brain, not because he wanted to build a
better theory about cognition, but because he had a concern
about out algorithms. Penrose felt that consciousness just can't be
explained by any rule based system. He pointed to an
idea called Girdle's incompleteness theorem, which said, look, there are
(06:13):
mathematical truths that we can see to be true, but
they can't be proven within mathematics. In other words, there
are many systems where we can see things to be true,
but the system itself can't prove them. You need to
somehow step outside of the system. Now, to Penrose, this
was a sign that human understanding operates in a way
(06:35):
that transcends computation. In other words, he said, brains aren't
just computers, and if they're not just computers, then the
mystery of consciousness might demand a different kind of physics.
So he wrote a very interesting book called The Emperor's
New Mind, which asserted that the brain can't just be
(06:57):
a computer. So in your Book's New Mind, which I
read as a young person and really loved, so you
argue that consciousness can't be explained by algorithms.
Speaker 2 (07:10):
So help us to understand that.
Speaker 3 (07:12):
But it really means, you see, an algorithm is just
the sort of technical word for a computer program. I
feel like maybe people use that term. It just means
that you have a rule which is a computational rule.
Speaker 1 (07:25):
Right, And why what made you feel that consciousness can't
be explained by algorithms?
Speaker 3 (07:30):
Well, it goes back to the Girdle the lecture that
Stein gave about Girdles theorem. And I realized that you see,
if you see mathematical proof, you could have a set
of rules, axioms and rules of procedure. These are of
a nature that you could put them on a computer.
Speaker 1 (07:51):
You think there are forms of human insight that fundamentally
cannot be replicated by algorithms.
Speaker 2 (08:00):
Is that that's correct.
Speaker 3 (08:01):
Okay, yes, absolutely right.
Speaker 1 (08:03):
Okay, great, and so and so that made you think
that maybe this mystery of consciousness needed to be taken
seriously by physicists and mathematicians. So, yes, So how did
you how did you start addressing this?
Speaker 3 (08:20):
I was trying to think about the laws of physics
that we sort of understand, and some of them are
very powerful. Well, even you turn in mechanics explains an
awful lot and science general theory of relativity explains a
lot more, and it's more difficult to apply things, but
(08:42):
it's still computational. What about quantum mechanics?
Speaker 1 (08:45):
Now, before we go further, I just want to give
a reminder about what quantum physics is. It's the branch
of physics that describes the behavior of matter and energy
at the smallest possible scales, at the level of atoms
and subatomic particles, and down there the world behaves nothing
like what we're used to. Particles can be in more
(09:07):
than one place at once. This is what's known as superposition.
Particles can become mysteriously linked across space in what's called entanglement.
And the most bizarre feature of all is that the
mere act of measuring a system seems to affect its outcome.
This is what's called the observer effect. In our current
(09:27):
understanding of quantum mechanics, the story is that until a
particle is observed, its properties don't exist in a definite way.
Speaker 2 (09:36):
They exist only in probabilities.
Speaker 1 (09:39):
In other words, a quantum particle doesn't have a precise
location until you look at it. Until that moment, it's
smeared across a range of possibilities, and then those possibilities
collapse to one outcome when you observe. Now, this isn't
just a metaphor. This general idea has been tested and
(09:59):
confirmed for over a century, and it's built into the
fabric of our technology. Quantum mechanics is the science that
allows the transistors in your cell phone, and the lasers
at the grocery store scanners and the GPS in your car.
Quantum mechanics is real, and it's very countereteitive, and it
seems to tell us that at the heart of reality
(10:21):
is a kind of indeterminacy, a fuzziness that only collapses
into certainty when it's observed. So think of it roughly
this way. You toss a coin in the air and
while it's spinning. It's not heads or tails. It's sort
of like it's both at once, but the instant you
catch it and look, it becomes just one heads or tails.
(10:45):
That moment of catching it is like the wave function collapsing.
Speaker 2 (10:48):
Now here's the thing. In quantum mechanics.
Speaker 1 (10:50):
There's no way to predict what the coin's going to be,
heads or tails, and so that non computable strangeness, that's
what Penrose was interested in. He wondered, what if that indeterminacy,
that collapse of possibilities into one real outcome, wasn't just
a physical process but also has to do with a
(11:13):
mental one. In other words, what if the flicker of
consciousness is related in some way to the collapse of
the quantum wave function. So back to Penrose talking about
(11:41):
his search for something non computable and getting interested in
the collapse.
Speaker 3 (11:46):
What about quantum mechanics? Then I thought, wow, I was
shruding no equation, that has no problem about putting that
on there. Maybe lots of parameters involved, it's make it tricky. Well,
that's a well determined determined It is a good question.
Roading equation doesn't give you what happens in the world.
Why doesn't it give you what happens. Schrodering himself was
very keen on explaining these things and his well known cat.
(12:11):
He was making this is an absurdity. To have a
cat which is dead and alive at the same time
is a nonsense. This is point of what he was
trying to make. He was saying, this is an absurdity.
His equation he was trying to say. He was saying,
roughly speaking, my equation does not describe reality. There is
(12:32):
something more. And this something more is what we tend
to call the collapse of the wave function. You're a
wave function drugs along and behaves according to the Schroding
equation very reliably and honestly, and then from now time
to time it says, whoops, I'm going to do something else,
and then it becomes probabilistic, and it's all hidden in
(12:54):
all sorts of man and manical schemes.
Speaker 1 (12:58):
So you mean is that classical computation can't explain consciousness,
and so the question is then what can? And this
is where you make the fascinating proposal that quantum mechanics,
and specifically the collapse of the wave function, might be
involved in consciousness.
Speaker 3 (13:17):
See people say sometimes I'm just not say, well, here's
the problem, and here's a problem. So they're the same thing.
It's not that it's that we need something which is
not a computable part of physics. What is it in
the physics that we know it would not be possible
to put on a computer. Well, you see, if the
collapse of the wave function is purely random, then you
(13:38):
could put it on a computer source off. And it's
not perhaps really random, it's something very subtle, and you
need that for the collapse of the wave function. And
the story has developed in other ways beyond what I had.
Then you see, this was the beginning of the story,
and you're asking me about the beginning. The beginning was
the story. It was a little bit in the sense
(14:00):
that I didn't know really much about what to do.
I could see that in according to my new point,
the collapse of the wave function had to be a
major part of the physics which is responsible for evoking consciousness.
Speaker 1 (14:18):
So to summarize where we are, Roger felt certain that
consciousness couldn't be explained just by classical computation. Again, most
of quantum mechanics you can easily model on a computer,
like the evolution of the Schrodinger wave function, but there's
something very weird about the collapse. That's the part you
can't compute. So Roger felt he was onto something interesting there.
(14:41):
So he sat down and wrote The Emperor's New Mind,
and the title, as you might guess, was a reference
to the story of the Emperor's New Clothes. The idea
being that everyone is assuming we can explain consciousness by
putting together enough neurons, but in fact, in his view,
the burr is naked consciousness possibly can't be explained by
(15:04):
just a bunch of neurons. So I asked Roger what
happened just after he published the book In nineteen eighty nine,
I wrote.
Speaker 3 (15:11):
My book Them Prisoner Mind and hoping some young people
might be stimulating, and only got old retired people. I
thought I'd done lo It was sort of a fairly
reasonable job as an ignoramus, but not too bad at
a job of trying to learn the main features of neurophysiology.
Speaker 1 (15:27):
So Roger started studying up on the brain, really as
a side gig to his mathematical physics career. But the
more he looked at it, he thought that maybe the
macro level at which we were able to study.
Speaker 2 (15:38):
The brain wasn't really revealing its secrets.
Speaker 3 (15:41):
And I would say that it has a genuine, deep purpose,
and that purpose is not clearly revealed in the structures.
But it's not something which is obviously like a computer.
Something else going on. But I didn't know what was
going on. I had no real idea by the time
I got to the end of my own presuming but
(16:02):
I just I might. I could have stopped writing in
this point, and I said, well, that's I've written so
much so far.
Speaker 2 (16:07):
I better go on.
Speaker 3 (16:09):
And so I'm more or less sort of some idea
which I didn't really believe. I tried to think of
something that might be non computable, you see.
Speaker 2 (16:16):
So that's where things were for Rogers' idea.
Speaker 1 (16:19):
He suspected there must be some kind of quantum effects
in the brain, but he didn't know where to look.
But at the same time, in America, there was a
young antesthesiologist named Stuart Hammeroff who was interested in consciousness.
Speaker 4 (16:32):
And I got interested in consciousness, and I went to
med school and was interested in neurology, neurosurgery, psychiatry. But
I didn't like those lifestyles, particularly what they got to do.
They didn't actually get to do the surgency, but the
neurologists in particularly didn't have much to do. And I
took a research elective over summer in a cancer lab
(16:53):
and studied my toasters. I figured just try something different,
and so we uh studying cell division. And as you know,
the cell divide, the chromosomes are separated by these spindles,
which are microtubules.
Speaker 2 (17:04):
That's Stuart hammer Off.
Speaker 1 (17:05):
And while everyone in that lab was interested in the chromosomes,
where the genes are, he found himself interested in the microtubules. Now,
what are microtubules. The starting point here is that all
the cells in the brain, like neurons and glial cells,
are not empty. Inside every single brain cell is a
bustling inner world. You've got all kinds of structures that
(17:27):
help the cell keep its shape and transport materials around.
And among these structures are microtubules, which are tiny hollow tubes.
They're part of the cells skeleton. Sometimes people think of
these like the tracks that guide packages through a warehouse.
Now these are very very tiny. Each microtubule is about
(17:48):
twenty five nanometers in diameter, which means you can line
up four thousand of them across the width of a
single human hair, and they're long too, so they stretch
like tiny straws all through the interior of the neuron.
Now what's amazing is these are constantly assembling and disassembling themselves,
almost like living legos, and this adjusts the internal architecture
(18:11):
of the cell in real time. So Stuart got interested
in these microtubules and wondered if they were more than
just railroad tracks.
Speaker 2 (18:20):
Back to Stuart Well.
Speaker 4 (18:21):
Micro teams are found in all cells, including neurons, which
are full of them, and they are like the skeleton
and the scaffolding on the cell, but they're also the
nervous system of the cell. They organize things, and their
structure I learned back then is a lattice kind of
like a computer lattice, where you have individual units proteins
called turbulence that I thought back then can be in
(18:43):
two states, like flexing like a peanut open and closed,
and that would be like a bit at one or zero.
Speaker 1 (18:49):
So Hammerff is looking carefully at these and he proposed
that microtubules might be doing something beyond structural work, that
instead of just looking at the microtubule as a roadway,
you might think about the details of the microtubules and
ask whether this could be a structure that was a
lot more interesting than it first appeared. So he started
(19:11):
modeling tubulens, the little bricks of microtubules, and came to
the conclusion that you could store something like ten to
the sixteenth bits of information in a single neuron using microtubules.
And this was essentially the number that people were talking
about for the storage capacity of the entire brain.
Speaker 2 (19:29):
Now, his colleagues were skeptical. They didn't want to hear it.
Tell me to get lost.
Speaker 4 (19:32):
So except then one day, fateful day, this guy said
to me, Okay, why is that asked? Let's say you're right,
how would that explain consciousness? How would that explain love, feelings, pinkness, joy,
blah blah blah. Essentially the hard problem five years before
Dave announces. But you knew the problem, I said, WHOA,
you're right, I have no idea. I was a reductionist nudgeon,
(19:55):
and I was ashamed of myself.
Speaker 1 (19:56):
Actually, so we actually just want to say, I want
to make sure everyone's following. So the hard problem of
consciousness is you've got all this physical stuff happening in
the brain, why does it feel like anything.
Speaker 2 (20:05):
Why do we have experience? That's the hard problem.
Speaker 1 (20:07):
Okay, Right, so you were looking at these microtubules which
are made up of these tubulin peanut shaped proteins, and
you're saying, hey, there's something really interesting here. But it
didn't solve the hard problem.
Speaker 2 (20:18):
Right.
Speaker 4 (20:19):
So I was just saying, more computation, more information processing.
So and the guy had a beautiful point, and I
was kind of stunned. And he said, you should read
this book by Roger Penrose called The Emperor's New Mind.
I said, I've kind of heard of that guy. So
I bought the book. I read it, and I was
kind of blown away. I mean, it's an amazing book.
The first half is about why consciousness is not a computation.
(20:41):
He used something called Girdle's theorem from mathematics, which said
a mathematical theorem cannot prove itself. You need somebody or
something outside the system, like a mathematician, to say yeah,
it's true or not. And he extrapolated and said it's
like understanding, you know, to understand something, you need to
be outside the system, very similar to John Searle's Chinese
room argument. You know, the guy has the Chinese symbols.
(21:02):
He looks them up and he translates, but he doesn't
understand Chinese.
Speaker 2 (21:05):
So that's the sense just doing computer operations, right.
Speaker 4 (21:08):
And so that was the difference and Roger. So the
second half of the book was Roger's solution, which had
something to do with quantum physics and collapse of the
wave function, the measurement problem in quantum Kinnis, which was
a whole other mystery. But he said, the solution to
that mystery is the same as is for consciousness. But
Roger didn't have a biological structure that could be at
(21:29):
the quantum level. And he said in the book, I
don't know what it is. Maybe somebody does. So I
read the book and I said, holy crap, he needs microtubules.
I've been studying for twenty years.
Speaker 2 (21:37):
So Stuart wrote Roger a letter.
Speaker 3 (21:40):
But then Stuart Haerrov read my book and wrote back
to me said, evidently you don't know about microtubules. He
was absolutely right. If I'd known about microtubules, that's it.
Here's a much better bet. For various reasons, they are
probably because they're too See. It seemed to me that
(22:02):
there is a much better chance you could isolate quantum effection.
Speaker 1 (22:06):
So they met up in England and Roger was very
taken by the geometry of these microtubules. Tell us what
is special about microtubules?
Speaker 3 (22:16):
Well, what's special about microtubules? There's several things which excited
me about them. Some of them are sort of peripheral,
but not so stupid. Maybe they are two to begin with,
and that struck me as much better chance preserve coherence.
You see, if you're going to have the collapse of
the wave function, you've got to have a well defined
(22:37):
wave function which isn't collapsed by the environment. You see,
normally what happens is that the environment collapses that and
that's no use to anybody this standard, As I say,
Ladi von Neumann arguments, do you say that the collapse
occurs because the environment gets involved? You have no control
over the environment and so therefore it behaves randomly in someone.
Speaker 1 (23:00):
In other words, he's pointing out that the environment normally
collapses the wave function very rapidly. But he appreciated the
possibility that microtubules might serve as a wave guide, which
means there's something about the particular structure of these long,
thin straws that keeps the wave function uncollapsed for a
longer time. A.
Speaker 3 (23:21):
Their tubes. B. They have a very symmetrical structure of
the tubulence, and they combined together in this particular structure,
which I found fascinating because it has, for example, symmetries
in three different directions. One is along the axis, one
(23:43):
is twisting one way, and the other is twisting the
other way. So it just struck me what's funny about
these microtubules. You have these microtubules which have one direction
along the tube, and that seems mirror what you get
in these tubes, that they become super conductive. So this
(24:03):
suggested to me that maybe there is some quantum super
conductive effect along the tubes, which is quite different from
nerve transmission, which is absolutely a quantum effect.
Speaker 2 (24:18):
So the idea is you've.
Speaker 1 (24:18):
Got these microtubules which are inside all the neurons and
these conservative waves guides. One of the criticisms that people
have had about quantum mechanics in the brain is they say, look,
it's too warm and noisy in there.
Speaker 2 (24:34):
What do you say in response to that.
Speaker 3 (24:38):
Well, that's a general comment you might expect that applies
if it hasn't gone some very very specific structure, and
the market tube was I thought, much better chance of
that sort of thing. I mean, they're doing a pretty trick,
pretty good trick, you see. If they actually are preserving
coherence along the tubes, this is a neat trick that
(25:00):
nature allegedly. I'm saying that to say that's my viewpoint,
must actually have succeeded and making this trick. I'm The
general comment is warm and messy, sure as a whole,
but there are structures when this warm and messy thing.
You don't need the whole thing to be structured in
this way. You just need certain elements in this complicated structure,
(25:24):
which as a whole may be warm and messy and
all sorts of things. But there are things, the claim goes,
which can preserve quantum coherence. And the idea is that
maybe microtubules do. And when I heard about them from Stuart,
I thought that was a much better case than anything
I'd seen before.
Speaker 1 (25:40):
So hammer Off and Penrose got interested in this possible
relationship between microtubules and quantum mechanics. But what does any
of this have to do with consciousness? Back to my
interview with Stewart in quantum Mechanics, things can be in
different positions. The wave function predicts how that moves along nicely.
But what happened as you get a collapse of the
(26:01):
wave function, which tells you, hey, let's say the particle
is over here, over here, and the idea was the
collapse that moment when that happened, there's some consciousness in
the universe.
Speaker 2 (26:14):
That's what he predicted. That's what he predicted.
Speaker 4 (26:16):
People are saying conscious comes to the outside and causes
the collapse, but that puts consciousness outside science. It's a
dualist position. And actually one of the charmers takes now,
but it goes back to Vignaer and von Norman and
Boord early part of the twentieth century and then and
others had didn't want collapse to deal with it or consciousness,
(26:36):
so they just said many worlds, it's easier to think
about the consciousness. And Roger came up with a solution, says,
the separations are unstable and will collapse and give consciousness
and due to an objective threshold given by the indeterminacy
principle one equation.
Speaker 1 (26:53):
Okay, and so who is experiencing the consciousness or the
quality of when there's a collapse of the wave function.
Speaker 4 (27:00):
The collapse itself is who's is who, what is experiencing.
I don't think it is controversial. I don't think there
needs to be a separate self. Other people disagree with
me on that, but I think if you have a
sequence of experiences and memory, you have a self. You
know who you are, you know when you wake up
the morning, the same person moment to moment. So I
(27:21):
don't think there's any separate entity as the self. I
think just I think you have a sequence of experiences,
complex experiences. I should go back and say when, when
when the objective reduction that's his name for objector threshold,
quantum state reduction, objector reduction, or or when that occurs
in the environment and in the chair anywhere other than
(27:45):
in particular arrangements. It's the experience is random, fleeting, disconnected.
It comes and it goes. It's apparently happening all around us.
We never noticed. It's like and that was proto conscious,
so that they call that proto conscious, and I liken
that too. If you go to the symphony and the
musicians are tuning their instruments before and you hear all
(28:06):
this to me noise to train the musicians different. But
to me, it's like uh uh, you know, it's it's
noise and then they start to play and it's Broms
or Beethoven or whatever, and uh. And that's what the
brain does, that's what the micro tubuas do. Orchestrates the
objective reduction. Hence the theory is orchestrated objective reduction.
Speaker 1 (28:26):
Okay, so when there's the collapse of the wave function,
there's a little bit of consciousness. But if you build
a device in the right way where you've got all
these microtubules that are guiding this, that are orchestrating this
whole thing, then you get something like our contry and
they have to they.
Speaker 2 (28:42):
Have to be entangled.
Speaker 4 (28:43):
So the superposition states become part of one one much
more complicated state. So when you when we're collapsing our
conscious moments, now there's a lot of richness in it.
I see you, you see me, I see this stuff
behind you, et cetera, et cetera. And so and there's sound,
there's different senses. It's all orchestrated. I would say integrated,
but that's a different theory. It's more orchestrated.
Speaker 1 (29:05):
Now, what would that get us to have entanglement across
different regions of the brain. Well, one example Stewart turns
to is what's called the binding problem. The binding problem
is a long recognized mystery that different regions of the
brain encode very different types of information like.
Speaker 2 (29:24):
Movement here, and colors here.
Speaker 1 (29:27):
And face recognition and sound and touch, and yet you
enjoy a totally unified experience. For example, let's hey watching
a basketball player race down the court dribbling the ball.
Different areas of your brain are processing the shape and
the movement and the sound of the ball hitting the court,
but you perceive the whole thing as one guy racing
(29:50):
down the court. The colors and the motions and the
sounds don't separate off from one another. So how are
these distinct features processed in total different brain regions integrated
into one seamless perception. This remains a central mystery in neuroscience.
So how might their theory address.
Speaker 4 (30:11):
That spatial temporal binding? You know, you see something moving
through the sky and its shape, color, motion, meaning or
processed at different places at different times in the visual
cortex and cortex in general. And yet we see one object,
we see a yellow kite fluttering instead of yellow kite
fluttering move. We see one thing instantaneously, so it's it's
integrated or orchestrated in time, and also in different regions
(30:36):
of the brain. So I think the brain needs entanglement
one way or the other.
Speaker 1 (30:39):
So, in other words, neuroscience traditionally just thinks about neurons,
and those are in some sense quite slow.
Speaker 2 (30:46):
But maybe Hammers.
Speaker 1 (30:48):
Suggests there are much faster processes. They're binding things together.
Speaker 4 (30:53):
It's more like music. It's more like resonance harmonics, interference beats.
In fact, to get from the very fast and very
slow interference beat, it's probably what does it. So I
think the brain is more a quantum orchestra than a computer.
Speaker 2 (31:06):
Got it.
Speaker 1 (31:07):
And so essentially all our technologies are just measuring what
neurons are doing. Like you dunk electrode in and you
see the spike head of the neuron.
Speaker 4 (31:14):
And so they're only listening to the base and percussion
of the symphony. They're missing the flutes and the piccolos
and everything else. And what makes you think this The
other theories don't work. All the other theories are based
on a neuron firing is a bit or a neuron
is essentially a one or a zero. And if you
look at a single cell organism like a paramesium, it
(31:37):
swims around, It finds food, it finds the mate, it
has sex, it can learn. If you suck it into
a capillary tube, it gets out faster and faster each
It's one cell, and it does all that with its microtubules,
whether it's silly and it's internal microtubules. So if a
paramesium can do that, and are you serious and thinking
that a neuron is a one or a zero and
that's it, it's an insult in neurons.
Speaker 1 (32:15):
So together, Penrose and Hammeroff worked on their idea of
entanglement going on.
Speaker 2 (32:19):
Across the brain.
Speaker 1 (32:21):
And the hypothesis is that these deep tubes humming away
deep inside the brain's machinery, these orchestrate when and what collapses.
So they call this orchestrated objective reduction. Give me the
idea of orchestrated objective reduction?
Speaker 2 (32:39):
What does that.
Speaker 1 (32:40):
Mean and how does that explain consciousness potentially?
Speaker 3 (32:44):
Okay, think of as I used to play ping pong
when I was at school, for instance. You see, as
I never achieved any great skill with this, but I
can understand there's just a game where you have to
act very quickly, and the way if I flick the
ball into the right hand corner as opposed to the
(33:06):
left hand corner, it's because I think by looking at
my opponent that he's not expecting it for me to
flick it into the left hand corner, and so I
do that flick into that corner because I think from
what I've just gained it's very small fraction of a second,
much less than half a second. I estimated that this
(33:26):
is a good thing to do, so I think that
was a conscious choice. Now, what is the current view
amongst I believe, and I get this from Stewart. The
current view amongst neurophysiologists is that these actions are not conscious,
they're much too quick. But Stewart's view and mine is
it is conscious, but it can only occur because of
(33:51):
the following mechanism. The argument would be that you could
preserve quantum coherence at a big level that is sufficiently
isolated from the outside world that in this layer you
could preserve a lot of quantum coherence, so that this
would mean that the action of flicking the ball this
(34:12):
way rather than that way, and this choice is it
made conscious consciously. The current view is there's no time,
that the consciousness come about, much too late for this.
But our view is no, there is time because the
choice of which action to take can be a conscious one.
(34:34):
The action taking involves a lot of nerve transmissions and
making your this way rather than that way, and all
these things. I think of a tennis player deciding to
go cross court rather than the bat down the line,
and that involves different muscle muscle actions. Now those different
muscle actions can be in superposition, kept in superposition, so
(34:58):
which one of them is truck It can be done
very quickly and those then the actions take place and
the person that's what has decided to be done. So
although the conscious action to move all those particular muscles
like this, and that's not conscious, what's consciousness. I'm going
to flick the ball to the right rather to the left.
(35:21):
And so that is a whole lot of different motions
which are all together in superposition. So this is the
idea that this collection of motions and that collection's motions
and which ones are activated are all there together, and
which one is activated is a conscious choice. And that
conscious choice, as it is at a quantum level choice
(35:44):
in these very specific cells that you get the coherent
superposition of different actions. So it could be this it's
under control all this one or this one, and they're
all there in quantum superposiniess. So the choice you make
as to which one is controlled is a quantum choice.
Speaker 1 (36:05):
And presumably when when the waveform collapses, that's when you
become conscious of something.
Speaker 2 (36:12):
That's that's the idea. Yes, that's what it is.
Speaker 3 (36:15):
Consciousness is to do with the actual collapse.
Speaker 1 (36:18):
One intriguing thing is that this proposal seems to blur
the line between physics and philosophy in an interesting way. So,
if consciousness arises through quantum processes, does that suggest that
consciousness is not just a feature of brains, but a
more fundamental property of the universe.
Speaker 2 (36:41):
How do you see this?
Speaker 3 (36:42):
Yes, but you see, But it might be you've got
to get it organized in a very subtle way in
order to reveal. You see, the collapse part of it
might be easy to reveal, but the way in which
it's not quite random and quite random, probably in a
very sophisticated way.
Speaker 1 (37:01):
Does this hypothesis have implications for free will?
Speaker 2 (37:08):
That's a very good question.
Speaker 3 (37:10):
You see, I'm even quite recently sort of changed my
view on this question. I often thought it's a sort
of meaningless question in a way. I mean, does it
mean that a quantum effect is brought into play because
quantum thing is not deterministic? And does the fact that
it's not deterministic mean free will? Not normally because it's random?
(37:32):
And if it's random, that's not free will. I mean
you're just tossing a toy. It's not random because it's
got to be doing something. I mean, randomness isn't beneficial.
Speaker 2 (37:43):
In a way.
Speaker 3 (37:44):
You see, you could make it random, but that's not
the point free will. You could say that, you see,
people often say that free will could be there if
it's not deterministic, but it doesn't know you any good
if it's just right. So the view I have is
more or less this. It's not even money. It's a
(38:06):
very recent view, I think. But the view is more this.
There is something rtrachursal about it. What free will really
means and what I'm arguing for here. It's not that
you can do anything you like, and you can act
randomly if you like. You're doing what you think is
the right thing to do, so you have the free
(38:27):
will to do what you think is the right thing
to do, and it doesn't necessarily be righteousness center virtuous.
It means, in your judgment, the correct thing to do.
Whether it's correct, desper for or beneficial less or for
the goodest, the whole, or whatever, that's not the point.
The point is that you are doing it because you
(38:47):
think it's the right thing to do. Now that means
you're understanding it.
Speaker 1 (38:53):
What kind of experimental result would excite you most in
the coming years.
Speaker 3 (39:00):
I think if you're looking at things plausible within current technology,
maybe some convincing kind of quantum coherence within microtubules.
Speaker 2 (39:09):
I want to ask you about AI.
Speaker 1 (39:11):
We've seen such incredible progress in classical AI systems, but
given your view that consciousness involves non computable processes, do
you think that AI is conscious, could be conscious or
is it just an impressive simulation.
Speaker 3 (39:31):
No, in one word, it's not conscious, and it's not
going to be conscious by having more and more and
more elements in your computers.
Speaker 1 (39:42):
So could a quantum computer in the future. Could a
quantum computer be conscious if it were designed with the
right architecture or is something else still missing?
Speaker 3 (39:50):
You have to be careful about what you mean by
a quantum computer, because I don't think quantum computer in
the sense that people use that term does actively role
using the collapse of the wave function as part of
the mechanism in quotes, because it's not really a mechanism.
Speaker 2 (40:07):
That's right, Yeah, okay, got it.
Speaker 1 (40:09):
So the kind of quantum computers that for example, Google
is working on now, because presumably it doesn't involve the
collapse of the wave function, you think it wouldn't be
conscious as such.
Speaker 2 (40:22):
Yes, that's right, Okay, great.
Speaker 1 (40:24):
I asked Stuart the same question about whether contemporary AI
could be conscious.
Speaker 4 (40:30):
Not with the kind of computers we am now, not
with a silicon based And you know, our friend Dave Chalmer's,
after decades of the heart problem, recently came out and said,
well AI consciousness is inevitable and throwing the heart problem
under the bus.
Speaker 2 (40:46):
Totally interesting, and then backing up and.
Speaker 4 (40:50):
When I questioned him about it, he said, well, what's
the fundament there's no fundamental difference between silicon and carbon.
Speaker 2 (40:56):
I said, wrong answer today. First of all, it's not carbon.
Speaker 4 (40:59):
It's organic carbon, which means aromatic rings, which means quantum.
So that and there's a huge difference between organic carbon
and silicon. Silicon can't do that. So and this organic
carbon aromatic hydrocarbons have been in the universe right from
the start.
Speaker 2 (41:17):
So let's summarize.
Speaker 1 (41:19):
According to this idea from Penrose and hammer Off, the
brain isn't just a network of firing neurons. It's also
a kind of quantum computer. Inside every single brain cell
is a whole world of microtubules, these tiny cylindrical structures
that are so small they've traditionally been ignored. But maybe
(41:40):
they suggest these structures are doing more than organizing the
cell's interior. Maybe these microtubules are hosting quantum processes. Maybe
they're sustaining delicate quantum states long enough to do something
meaningful and entangling across cells, and that the collapse of
(42:00):
these states might correspond to moments of conscious experience. Now,
I just want to repeat one point. You might be thinking, Wait,
doesn't quantum physics get washed out in warm, wet environments
like the brain. That's a reasonable objection. In fact, it's
one of the main reasons that many scientists have been
skeptical of the orchestrated objective reduction theory. Quantum coherence usually
(42:25):
does not last long in messy biological environments.
Speaker 2 (42:28):
It's fragile.
Speaker 1 (42:30):
But on the other hand, that skepticism has been challenged
in recent years by findings in other parts of biology.
Quantum effects have now been observed in photosynthesis, in bird navigation,
in the sense of smell. Somehow, living systems might be
more hospitable to quantum phenomenon than we thought. And if
(42:51):
that's the case, then maybe, just maybe, the brain has
found a way to leverage quantum effects, not just for computation,
for consciousness itself. Now, Penrose and Hamros's theory and others
like it remain highly speculative. Neuroscience continues to make great
progress without invoking quantum mechanics artificial neural networks, which are
(43:14):
entirely classical in their architecture. These have achieved unbelievable feats
like the modern blossoming of AI. But so far as
we know, artificial neural networks like CHATCHPT are not conscious,
and so the idea here is that we need to
think not just bigger, but perhaps also sub microscopically smaller.
(43:36):
So we've just heard from two thinkers who aren't afraid
to step beyond the comfortable borders of their fields. To
probe around in areas that most scientists won't touch. What
I find so compelling isn't the certainty of the theory.
It's the audacity of the question. It's the willingness to say, look,
perhaps our current tools aren't enough. Maybe consciousness isn't just
(43:59):
a clever computation, but something much stranger. Maybe the deepest
puzzles in neuroscience can't be solved without rethinking everything from
the ground up. There's a long history of big leaps
in science, beginning with questions that sounded naive or mystical.
There was a time when most of the ideas we
(44:20):
take for granted today were ridiculous. So I want to
return to one last thought from Roger. What advice would
you give to young scientists who are drawn to the big,
risky questions about consciousness but are afraid to step too
far outside conventional boundaries.
Speaker 3 (44:37):
To try and do the following. You will have some
specialist view that you see in order to make progress,
you have to dig deeply in a certain area and
understand that area as well as you can and better
than most other people. But you also, at the same
time should keep a broad outlook of what's going on
in the outside world and pick up maybe if you
(45:01):
see something which might connect with what you're doing.
Speaker 1 (45:03):
There are plenty of critics of this idea who point
out reasonably that there's not enough experimental evidence to take
this idea with the requisite seriousness yet. But it's okay
to explore the speculative as long as we keep one
foot planted in the empirical. It's a key to making
progress in science is balancing skepticism with curiosity and openness.
(45:26):
All of us in neuroscience like to believe that we're
close to cracking the puzzle of consciousness, but the fact
is we're probably just at the foot of the mountain,
and it's always possible, just like in any field, that
we're not even asking the right questions.
Speaker 2 (45:40):
Yet.
Speaker 1 (45:41):
What if we've been looking at the hardware in an
incomplete way and missing the best tricks of physics. The
fact is that the central mystery of neuroscience, for which
no one has a good answer, is the hard problem
of consciousness. Why if we have an organ that goes
around and collects information than a camera or a microphone,
(46:02):
why does it feel like something, presumably in a way
that your iPhone does not When it makes recording. Why
do we have private, subjective experience of the world. Quantum
mechanics may or may not provide the answer. Maybe we're
all just shooting in the dark until we discover a
new field and one hundred years from now called Schwanton mechanics.
(46:23):
But whatever the case turns out to be, it seems
likely to me that the neuroscience textbooks used by our
great great grandchildren will have very different stories than we
do today, and future centuries will look back on our
scientific frameworks with the quaintness that we look back on
ideas of flagiston or spontaneous generation, or that the Earth
(46:48):
was at the center of the universe.
Speaker 2 (46:50):
But the only way we're going to.
Speaker 1 (46:52):
Get there is to keep digging deeper and asking, by
not falling for the assumption that we've got it all
figured out with our stand in textbook models, but by
continuing to propose and put to the test brave new hypotheses.
(47:13):
Go to Eagleman dot com slash podcast for more information
and to find further reading.
Speaker 2 (47:18):
Check out my newsletter on substack and be a part
of the online chats there.
Speaker 1 (47:23):
You can watch the videos of Inner Cosmos on YouTube,
where you can leave.
Speaker 2 (47:26):
Comments until next time.
Speaker 1 (47:29):
I'm David Eagleman and this is inner Cosmos.
Host
David Eagleman
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