Chapter 4: Consciousness and the Physical

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Welcome to the Deep Dive.

Today, we're really plunging into one of those huge, persistent questions, aren't we?

We really are.

How does this intensely private feeling of being you, your thoughts, your feelings, how does that fit into the physical universe?

Yeah, it's like trying to, I don't know, weigh the feeling of hunger.

Exactly.

Put it on a scale next to a star or something.

It just feels like they belong in completely different worlds.

It's the ultimate mismatch, you could say.

And that's our mission today, isn't it?

To dive deep into how philosophy, and now science too, have tried to tackle this mystery of consciousness.

Right.

Using this fascinating chapter we've been looking at, it really walks us through the whole history, from ancient ideas right up to today's, like, cutting edge challenges.

And it's not just abstract stuff for academics.

No, definitely not.

This is about understanding reality, what it means to be alive, to be aware.

We'll touch on everything from, you know, the soul to quantum entanglement, even philosophical zombies.

It's quite a range.

Like the walrus said, shoes and ships and ceiling wax.

How does the mental fit in with all that?

Let's try to unpack it.

So maybe the first step is asking,

what is this mental stuff anyway?

Good starting point.

Let's use hunger.

Like you mentioned, everyone knows what that feels like.

But what kind of thing is that feeling?

Is it tall, wide?

Does it have a weight?

No, obviously not.

You can't measure hunger with a ruler or put it on a scale.

It's not a physical object.

And it doesn't act like physical energy either, does it?

It doesn't radiate.

It doesn't follow conservation laws.

There isn't a fixed amount of hunger you can have.

Right.

It's just different.

And another key thing is how you know you're hungry.

It's direct, isn't it?

Totally direct.

You don't need a blood test or some instrument.

You just know firsthand knowledge.

Unlike, say, knowing you have high blood pressure, you need a machine for that.

Exactly.

And maybe the most crucial point,

that knowledge is private.

Ah, yeah.

Only you feel your hunger.

Right.

People can guess, you know, if you're talking about food or rubbing your stomach.

Or maybe you're just a good actor pretending.

Or genuinely starving but keeping a straight face.

They don't have your direct experience.

That's totally different from physical things like brains or particles.

Their properties are public, measurable by anyone with the right tools.

Okay.

So this privacy, this directness that applies to all our experiences, joy, pain, seeing red.

That's the idea.

That's what defines the mental, this subjective, private quality.

So given this sort of fundamental weirdness of the mental, how have people tried to make sense of it?

The most intuitive way, maybe, is just to say they're two different things.

Exactly.

That's dualism.

And it's probably the default view for most people throughout history.

It feels right somehow.

Goes way back, right?

Like the soul, the spirit.

The Greek psyche, the Latin anima, Plato, Augustine, filtering into religious traditions.

The idea of a non -physical true self that thinks and feels and maybe even survives the body.

But it was Descartes, René Descartes in the 17th century, who really nailed this down philosophically.

He did.

He gave it a proper structure.

He talked about two distinct substances.

Res extensa and res cogitans.

That's it.

Res extensa, extended stuff.

Physical things, things that take up space, have width, length, bodies, rocks, planets.

And res cogitans.

Thinking stuff, mental stuff.

No extension, no location in space.

But it's what does the sensing, thinking, feeling?

Crucially, for Descartes, these were independent.

The brain was just matter, complex clockwork, maybe.

But the mind was something else entirely,

different stuff, which allows it to survive death, in his view.

And he had arguments for this, his famous malicious deceiver thought experiment.

Something right, where he doubts everything, his senses, his body, the world.

But the one thing he couldn't doubt was that he was doubting.

The very act of thinking proved his existence as a thinking thing.

Cogito ergo sum.

I think, therefore I am.

Exactly.

Since he could be certain of his mind, but doubt his body, he figured they must be distinct.

It's pure Matrix stuff, really.

Neo doubts the world, but never his own experience.

And Leibniz had that other argument, the mill.

Ugh, Leibniz's mill, yeah.

A powerful one against materialism.

Imagine a thinking machine, blown up to the size of a mill.

You walk inside, look around.

You'd just see parts moving, gears, levers, or neurons and synapses, in a brain analogy.

Precisely.

You'd only see physical mechanisms.

You'd never bump into the feeling of pain or the experience of seeing blue or boredom.

So how could feelings arise just from physical parts?

For Leibniz, they couldn't.

This dualist view had a huge impact, didn't it?

It sort of freed up science.

It really did.

It let scientists study the body as a machine, without treading on the toes of theologians worried about the soul.

A neat division of labor.

Though maybe it led to that hardware -software analogy for brain and mind, which you mentioned can be a bit misleading.

It's seductive, but yeah, potentially problematic.

But dualism itself has a massive problem.

It's Achilles' heel.

How they interact.

Exactly.

Princess Elizabeth of Bohemia put it straight to Descartes.

How can this non -physical mind stuff possibly push around physical body stuff?

Yeah, because physics tells us that to make something move, you need to transfer energy or momentum.

Right.

Where would this mental energy come from?

How does it interface with neurons without violating basic physical laws like conservation of energy?

There's just no evidence for that kind of interaction.

So if the mind can't causally affect the body, what then?

Then consciousness becomes causally impotent.

A ghost that can't even rattle its chains.

Your feeling of wanting to raise your hand doesn't actually cause your hand to go up.

It's just the sort of side effect of the brain processes that do cause it.

Like the steam whistle on a locomotive.

It accompanies the train's movement, but doesn't drive it.

Perfect analogy.

Consciousness becomes an epiphenomenon.

Your feelings, your subjective experiences, they make no difference to the world.

They serve no function.

That feels deeply counterintuitive.

And what about the immortal soul aspect?

If it's non -physical, how does it hold onto memories, your personality, after the brain decays?

Good question.

Where do those memories physically reside if not in the brain?

And where was this soul before birth?

After death.

If there's an afterlife, which version of your body does it connect with?

The questions pile up.

It reminds me of that neuroscientist stictum mentioned in the chapter.

Ah yes.

No brain, never mind.

The idea that consciousness needs some kind of physical substrate.

It could be neurons, could be silicon chips, maybe even something more exotic like quantum states.

But something physical seems necessary for experience to happen.

That seems to be the prevailing scientific view, yes.

Which leads us away from dualism and towards physicalism.

Right.

The idea that at the end of the day, everything is physical.

Back to Democritus.

Atoms and the void.

Pretty much.

Everything from stars colliding to you loving your family is ultimately explainable by physical processes and quantities.

Observer independent descriptions.

It's definitely simpler than dualism, just one kind of stuff to worry about.

And I guess for many it feels like the default in the scientific age.

It's often seen that way.

It's kind of a promissory note that science will eventually explain everything, including consciousness, using natural laws, no need for souls or spirits.

But even physicalism runs into some tricky territory, especially with modern physics, right?

Quantum mechanics.

Oh, absolutely.

Classical physics assumes objects have definite properties, locally determined whether we look or not.

But quantum mechanics throws a wrench in that.

Heisenberg's uncertainty.

And non -locality.

That's the really strange one.

Confirmed by those Nobel Prize winning experiments.

Entangled particles.

Stay connected, even when miles apart.

Measuring one instantly affects the other.

Faster than light could travel between them.

It's bizarre.

Spooky action at a distance, Einstein called it.

It fundamentally challenges the classical picture of physical reality.

So what could this mean for consciousness?

People like Roger Penrose think there might be a deep connection.

Penrose and others speculate, yes.

Maybe consciousness is linked to quantum processes in the brain, like the collapse of the wave function.

It's controversial, because brains are generally seen as too warm and wet for delicate quantum effects to survive.

But the possibility is there.

That the brain might use quantum resources somehow.

It's an open question.

Could it explain things?

Maybe offer computational advantages?

We don't know yet.

But it complicates a simple classical physicalism.

Okay, but staying within more standard physicalism, there's reductive physicalism.

Mine just is brain states.

That's the strong version.

Every mental state corresponds directly to and is nothing more than a specific physical brain state.

Your feeling of joy is neural firing pattern X.

Period.

Which can lead to this eliminative idea that once we understand the brain perfectly… We won't need psychological terms anymore.

Talk of beliefs or desires or even pain will just be replaced by neuroscience and ultimately physics.

Mental states become kind of unnecessary concepts.

So the feeling of a toothache is just identical to the groaning, the physiological changes, the avoidance behavior, nothing more.

In that strict view, yes.

Once you explain the physical and behavioral stuff, the job's done.

There's no extra feeling left over to explain.

Some philosophers, like Dennett, basically say subjective experience qualia is an illusion.

Dennett is famous for that stance, yes.

The redness of red, the painfulness of pain.

He argues these are illusions generated by the brain's complex processing, not fundamental realities.

Now, the author we're reading really pushes back against that, calls it absurd gaslighting.

Strongly.

The argument is that any theory that denies or dismisses the raw feeling of things like pain or despair or joy is missing the most important part of the human condition.

Think of accounts of severe depression, like Styron's darkness visible.

To call that experience an illusion seems inadequate, to say the least.

And there's the point about needing to bring experience back into understanding mental illness.

Neuroscience, knowing enough to intervene, but not enough to truly help without grappling with the patient's subjective reality.

Exactly.

Plus, there's that other problem for simple reduction.

Multiple Realizability.

Right.

The idea that pain isn't just a human thing.

Dogs feel pain, maybe fish, maybe even insects.

And their brains, their nervous systems, are wildly different from ours.

So how can pain be identical to one specific human brain state if it can be realized in so many different physical ways?

So it suggests a mental state, like pain can't be reduced to a single, unique physical state.

It's more about the function.

Ah, now you're leading into functionalism.

The computational view of the mind.

The mind as software idea.

Hillary Putnam.

That's the one.

It became huge in the information age.

The idea is that mental states aren't defined by the stuff they're made of, but by the job they do, their causal role in the system.

So pain isn't brain state X, it's whatever state functions as a damage detector, triggers avoidance, causes distress signals, etc.

Precisely.

What matters are the inputs, the outputs, and the relationships to other mental states.

The physical implementation, neurons, silicon chips, maybe something else is just a detail.

So if you programmed a Tesla with the right functional states.

Functionalism says it could in principle feel pain if its sensors detected damage, or tiredness if its battery ran low, provided it had the whole complex web of related functional states.

It's all about the computational role.

And this thinking underpins a lot of AI research and science fiction portrayals of conscious machines, doesn't it?

Blade Runner, X Machina.

Absolutely.

It's the dominant paradigm in many areas.

But it also faces a major hurdle.

The feeling part again.

The feeling part again.

The explanatory gap.

Why should this particular computation like monitoring body states feel like anything at all, let alone feel bad, like pain, while that computation, like calculating trajectory, feels like nothing?

Where does the subjective experience, the qualia, actually come from in a purely functional system?

Exactly.

It feels like a gap in the explanation like that Sydney Harris cartoon.

Step one, complex computation.

Step two, step three, subjective feeling.

I think you should be more explicit here in step two.

Which leads to Chalmers distinction, easy problems and the hard problem.

Right.

The easy problems are about explaining functions.

How we process information, control behavior, report mental states.

Science is good at those.

The hard problem is explaining why any of that processing should be accompanied by subjective experience, the what it's like aspect.

Chalmers thinks bridging that gap might be fundamentally impossible within our current physicalist framework.

And this ties into philosophical zombies.

The ultimate thought experiment for this gap.

Imagine a creature physically identical to you, molecule for molecule.

It behaves like you, talks like you, reacts like you.

But inside, there's nothing.

No consciousness, no feelings, just darkness.

Like a perfect actor or deep fake human.

Exactly.

Chalmers argues that such a zombie seems logically possible, there's no strict contradiction in the idea, even if they don't exist in our world.

But if zombies are conceivable, it means consciousness isn't automatically guaranteed by the physical structure and function alone.

It must be something extra.

An additional fact about our universe, beyond the purely physical facts as we currently understand them.

That's his conclusion, which suggests physicalism, at least in its current forms, might be incomplete.

So if dualism has interaction problems, and physicalism functionalism has this explanatory gap problem, where does that leave us?

Are older ideas coming back?

Interestingly, yes.

There's been a kind of renaissance for views that were considered, well, pretty far out for a while.

Idealism is one, the idea that mind or consciousness is fundamental and matter arises from it.

And panpsychism.

Panpsychism is getting a lot of serious attention now.

It's an ancient idea, really.

Instead of struggling to get mind out of matter, it suggests mind or some proto -consciousness, is a matter from the very beginning.

So consciousness, is it something special that emerges only in complex brains?

It's everywhere.

In rocks.

In electrons.

In its most basic forms, yes.

The idea is that the fundamental constituents of reality particles,

feels, have incredibly simple forms of experience.

Consciousness is ubiquitous.

Now it might not feel like much to be an electron.

I'd imagine not.

But the potential for experience is intrinsic to matter itself.

It avoids the hard problem of emergence, because consciousness was never absent.

That sounds counterintuitive, but maybe not actually inconsistent with science.

It's not obviously inconsistent, no.

And there's a related view, Russellian monism.

From Bertrand Russell.

And others like William James.

Russell argued that physics is great at describing the structure of matter, its causal relations, how it behaves, but it tells us absolutely nothing about the intrinsic nature of matter, what matter is in itself.

Okay.

So physics describes the outside view.

The external relational properties.

Russell suggested that the intrinsic nature of physical stuff, at least in complex arrangements like brains, is consciousness.

Consciousness is the inside view of the brain's causal structure.

So mind and matter are like two sides of the same coin, not two different substances, and consciousness doesn't magically emerge.

Exactly.

The physical description and the mental experience are just two ways of accessing the same underlying reality.

It elegantly solves the interaction problem, because there's only one kind of stuff involved, just viewed from different perspectives.

That does sound elegant, but panpsychism must have its own problems.

Oh, definitely.

The big one is the combination problem.

Meaning, how do all these little bits of consciousness in particles or neurons combine to form my unified consciousness?

Right.

And why only my consciousness?

Why don't the experiences of all the neurons in my brain somehow leak out and merge with yours, or with everyone else's?

Why doesn't the entire United States, with millions of conscious citizens, have its own collective consciousness?

We don't seem to experience a group mind when we're in a crowd.

No.

So how do these micro -experiences bind together to form larger individual minds, but then stop binding at a certain point?

What defines the boundaries of a mind?

And why do billions of neurons combine into a mind, but billions of stars in a galaxy presumably don't?

What's the difference?

Is it structure?

Function?

Material?

Panpsychism doesn't yet have clear answers to how this combination or boundary setting works.

It's a major challenge for the theory.

Wow.

Okay, so we've gone from the privacy of hunger, through Descartes' two substances, the rise and challenges of physicalism, the mind of software view, and back to these ideas where consciousness might be fundamental.

It's quite a tour.

It really covers centuries of intense thought.

And the amazing thing is, the questions are still very much alive.

The answers aren't settled.

But it feels like the approach is changing, with science really getting involved now, bringing empirical methods to bear alongside the philosophical arguments.

Absolutely.

Neuroscience, physics, AI research, they're all contributing new pieces to the puzzle, even if the overall picture is still forming.

So as we wrap up this deep dive, maybe the thought to leave with is this.

If physicalism as we know it is incomplete, if these other views like panpsychism or Rossellian monism have merit,

what kind of new understanding of reality might be waiting for us?

What framework could finally bridge that gap between the physical brain and the subjective feeling of being?

Especially, as you said, with things like AI forcing us to confront what consciousness really requires.

It really makes you think about your own experience, doesn't it?

How does all this resonate with your sense of being you?

What stands out from this whole exploration?

It's a question that keeps unfolding, pushing the boundaries of our knowledge about ourselves and the cosmos.

Well, thank you for exploring it with us on the Deep Dive.

We really appreciate you joining us and sharing your curiosity.

Until next time.