Chapter 5: What Truly Exists

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Welcome, Deep Divers.

Today, we're really plunging headfirst into a huge question.

What actually exists?

We're doing a deep dive into Chapter 5 of Then I Am Myself the World, which is titled, appropriately enough, What Truly Exists?

And our goal here isn't just, you know, talking philosophy in the abstract.

We really want to give you the core ideas that might just reshape how you think about consciousness, your own existence, even like the chair you're sitting on.

This chapter, it really pushes back against our everyday feelings about what's real.

It absolutely does.

And it's critical because, look, if you want to understand the mental consciousness itself, you really have to get a handle on existence first.

The chapter starts by drawing this really fundamental line in the sand, a core distinction between different ways something can exist.

That's the foundation for everything else we'll talk about today.

Okay, different ways something can exist.

That sounds big.

You're saying it's not just a simple yes, no, things exist or they don't.

What does it mean for something to exist for itself versus for others?

Right, it sounds simple, but there's a lot packed in there.

Let's take an example the chapter uses, which I think is quite vivid.

Imagine you're in a completely truly dreamless sleep.

In that state, there's nothing for you.

No experiences, no awareness.

You, the conscious you, simply don't exist for yourself.

But my body's still there, right?

Breathing, maybe snoring, someone else could see me.

Exactly.

Your body definitely exists for others.

People can observe it, interact with it.

But for you, intrinsically, there's nothing.

That's what the chapter calls relative or extrinsic existence.

It's derivative.

It depends on an observer.

Think about, I don't know, a star, a rock, your car, even a garbage can.

They exist, sure, but only in this way for others.

They don't have an inner perspective.

Okay, so that's extrinsic.

What about the flip side, intrinsic?

We'll contrast that with the moment you start waking up.

Maybe you're groggy, reaching for the alarm, bam.

In that instant, you pop back into being.

Your mind immediately exists for itself, intrinsically.

It doesn't need to be some profound mystical vision or a wild dream.

Just that basic feeling of being instead of not being is enough.

That raw awareness, that what it's likeness, that's intrinsic existence,

absolute existence, the chapter actually calls it the only existence worth having.

Wow.

Okay.

And you mentioned this distinction is formalized by a theory.

Yes, by integrated information theory or IIT.

And what's really different about IIT, what sets it apart from most other theories of consciousness out there, is where it starts.

Most theories look at the brain, the physical stuff, and try to figure out how consciousness somehow pops out of it.

IIT flips that script.

It starts with consciousness itself, with the undeniable reality of your subjective experience.

So if you start with experience as the fundamental thing, not the brain bits, what does that lead to?

I imagine some pretty unconventional conclusions.

Oh, absolutely.

It turns a lot of standard thinking out of Ted.

For one, starting with experience suggests that phenomenal experience, that subjective feeling, is probably much more widespread than we usually assume.

And IIT claims it's quantifiable.

You can actually measure it in principle.

It also implies that digital computers, the kind we use every day, likely have only a tiny, tiny amount of consciousness, if any.

And maybe surprisingly, it even opens up a new way to think about free will, though that's maybe a topic for another day.

And does the starting point help with famous hard problem of consciousness, the whole why does brain activity feel like anything question?

Exactly.

The hard problem, David Tolmer's term, asks why all that molecular or neuronal commotion, as the chapter puts it, should give rise to the feeling of pain or seeing red or anything at all.

Other theories really struggle there.

Why should physics suddenly create subjectivity?

It seems like a magic trick.

But IIT sort of sidesteps that.

By starting with intrinsic existence with experience itself, it doesn't need a miracle to bridge the gap.

It proposes that experience is an intrinsic property of certain kinds of physical systems when they're organized in the right way.

Okay, that makes sense.

It's not deriving consciousness.

It's saying consciousness is a particular kind of physical organization.

But any theory like this must have some basic assumptions about reality baked in, right?

What are they?

Good question.

Yes, there are core assumptions.

The first is pretty intuitive.

Realism.

Basically, the world is out there.

People, dogs, chairs, atoms,

they exist whether you're experiencing them or not.

You're closing your eyes doesn't make the room disappear.

The chapter contrasts this with solipsism, the idea that only your mind is real.

IIT dismisses solipsism as, well, ego infatuated and ultimately not helpful.

It doesn't explain anything.

Right.

And what about other big ideas about reality?

Like, are we living in a simulation that comes up a lot these days?

Where does IIT land on that?

The chapter tackles that too.

It acknowledges you can't logically disprove it, just like the old story of the philosopher dreaming he's a butterfly.

Is he a man dreaming or a butterfly dreaming?

But just because something's logically possible doesn't mean it's physically real or relevant.

The chapter compares it to angelology, historical debates about angels.

Interesting, perhaps, but sterile in explaining this world.

Basically, simulation hypotheses don't really help us understand the specific messy complex reality we actually seem to inhabit.

Okay, so realism is key.

What else?

You mentioned something about existence needing

causal power.

Yes, causal power.

This is absolutely central.

It's IIT's operational definition of what it means to exist fundamentally.

It boils down to the ability to both take a difference,

meaning to be affected by something, and make a difference, meaning to cause change in something else.

Ah, okay.

So affect and be affected.

Can you give an example?

Sure.

Think about something like, say, Santa Claus or an old scientific idea like the luminiferous ether.

Do they actually affect anything now?

Can anything affect them?

No.

So from IIT's perspective, they lack causal power.

They don't exist in this fundamental sense.

But take a hammer.

You grasp it.

It takes a difference from your hand.

You swing it and hit a nail.

It makes a difference to the nail.

That's tangible causal power.

It's how physics often works to stipulate the existence based on detectable interactions.

But what about abstract things, like the idea of God or the United States?

Surely they have causal power.

They make huge differences in the world.

Absolutely they do.

And the chapter addresses this head on.

The crucial point in how they have that power.

The causal power of God is wielded through the conscious minds of believers.

It's their belief that drives actions, builds temples, starts movements.

Similarly, the United States, as a concept passing laws, collecting taxes, waging wars, only has power because people consciously accept that it has these powers.

Take away that collective conscious belief and its power vanishes.

Think about just pieces of paper or digital entries, right?

Their incredible power comes entirely from the planet wide conscious agreement that they have value.

That's a really interesting point that consciousness underpins the causal power of these huge abstract concepts.

OK, so how do you measure this causal power, especially in something complex like the brain?

Well, it's defined operationally, though actually doing it is incredibly complex.

For a brain circuit, you'd theoretically have to perturb everything.

Turn individual neurons on or off, pairs, triplets, all combinations.

And then watch what happens.

What's the probability that neuron X fires if neurons Y and Z are active?

It's all about these conditional probabilities.

You tabulate all these cause effect possibilities into what's called the system's transition probability matrix or TPM.

This TPM is like the ultimate blueprint.

It describes everything the system can do, all its potential interactions.

In a deep sense, it defines what the system is.

It's a way of defining existence that actually has echoes all through science and even back to Plato.

OK, wow.

So existence is causal power described by this massive probability matrix.

Now, how does this connect back to actual experience?

You mentioned IIT starts with consciousness.

Exactly.

So having defined existence this way, IIT then says any actual conscious experience you have has certain essential properties.

It proposes five phenomenal axioms, things that are undeniably true about any experience.

Think of them like the basic axioms of geometry, but for the inner world.

Five fundamental truths of experience.

OK, what are they?

The first is intrinsically.

Your experience exists for you from your own perspective.

It's internal.

An outside observer can't fully access or be your experience.

Right.

Makes sense.

Number two.

Information.

Every experience is specific.

It feels a particular way.

Seeing red is different from seeing glue.

Hearing a C sharp is different from hearing a D flat.

If it were different in any way, it wouldn't be this specific experience.

It carries specific information content.

OK, specificity.

What's third?

Integration.

Every experience is unified as a single whole.

When you look around the room, you don't have separate experiences of the lamp, the book, the wall, all just added together.

It's one seamless integrated conscious field.

The chapter quotes Erwin Schrödinger on this.

Consciousness is never experienced in the plural, only in the singular.

It's always one scene.

One unified whole, even if it's complex.

Axiom four.

Exclusion.

Any experience is definite.

It contains exactly what it contains, neither less nor more.

You don't see things outside your visual field, for instance.

That information is excluded.

Even if you feel something vague, like a hunch, that feeling of vagueness is itself a definite, specific experience, distinct from other possible feelings.

It's precisely that So it has sharp boundaries, in a sense.

And the last one.

The fifth is composition.

Every experience is structured.

It's made up of parts, phenomenal distinctions and relations between them.

Think about looking at a lake scene again.

You distinguish individual trees, waves, the shoreline, the sky.

And you perceive their relationships.

This tree is to the left of that one, the waves are on the water, the sky is above.

There's a huge number of these distinctions and relations composing the overall experience.

Intrinsicality, information, integration, exclusion, composition.

So those are the undeniable properties of experience.

How does IIT link these to the physical stuff, the brain?

Right.

This is where the physical postulates come in.

There are five of them.

And they directly mirror the five phenomenal axioms.

The idea is, for a physical system, like a network of neurons, to actually have an experience with those axiomatic properties, the system itself must satisfy these five physical rules.

And these rules are all defined in terms of its cause effect power as captured by that PPM.

So the physical substrate has to have certain causal properties to match the experiential properties.

Precisely.

This physical substrate that satisfies the postulates is what we call the neural correlates of consciousness or NCC.

Though, again, IIT is technically agnostic, maybe complex tree roots or weird alien oceans could satisfy these postulates too.

But let's stick with the brain for now.

Okay.

So what are the postulates?

How do they mirror the axioms?

Okay.

First, for intrinsically, experience exists for itself.

The physical postulate is that the substrate must have cause effect power over itself.

Its causal interactions must be intrinsic to the system, not just driven from outside.

Second, for information, experience is specific.

The postulate is that the substrate must be in a specific state out of many possibilities, which determines its specific cause effect power at that moment.

Third, for integration, experience is unified.

The postulate is that the substrate's cause effect power must be irreducible.

It can't be broken down into independent non -interacting parts.

Oh, irreducible.

That sounds important.

Is that where phi comes in?

Exactly.

Irreducibility is quantified by phi.

That's the lowercase Greek letter.

Little phi measures how much a specific part or mechanism within the system contributes to the whole in an integrated way.

Then you sum up all these contributions across the entire system, and that gives you capital phi.

Capital phi is the measure of the total integrated information of the whole system.

It quantifies how irreducible, how integrated the system is.

So higher eyes means the system is more integrated, more irreducible, and therefore more conscious.

That's the core idea.

Higher eye corresponds to a greater capacity for consciousness, a richer experience.

Fourth, for exclusion,

experience is definite.

The postulate is that the substrate's cause effect power must also be definite.

It's specified over a particular set of elements, like specific neurons, and at a particular spatial and temporal grain.

This means there's a sharp boundary.

Certain neurons are in the NCC, contributing to the experience, and others are out, even if they're right next door and connected.

The chapter uses the US -Canada border analogy, close neighbors, but functional distinct entities.

So there's a specific set of neurons that forms the conscious substrate at any given moment.

Yes, and crucially, IIT proposes an extremum principle here.

Within your brain, there might be many overlapping groups of neurons that have some level of integrated information,

some IO value.

But consciousness, your actual experience, corresponds only to the single system that has the maximum value of Ike, the winning configuration, so to speak.

Any subsystems with lower Ike exist only extrinsically.

Nature picks the peak of integrated cause -effect power.

This applies to scale, too.

The system exists at the spatial and temporal grain that maximizes Ike.

Maximum wins.

Got it.

And the last postulate, for composition.

For composition, experience is structured.

The postulate is that the NCC's cause -effect power must itself be structured.

The way the parts interact, the whole web of causal relationships defined by the TPM, when you analyze it for its irreducible structure, it yields what IIT calls an A -structure.

This is like a complex geometric shape in a very high -dimensional space, representing the complete structure of causal relationships within the NCC at that moment.

A -structure.

Like the unique fingerprint of that conscious moment's causal web.

Exactly.

And this leads to IIT's most central and frankly radical claim, the explanatory identity.

It states,

is what the experience feels like from the inside.

All the qualities, the redness of red, the feeling of space, the flow of time, thoughts, emotions, they are the specific features of this incredibly complex causal structure.

Wow.

So it's not just correlated, it is the structure.

That's the claim.

Which implies something else profound.

Consciousness is non -algorithmic.

You can't just run a consciousness program on any standard computer because it's not about computation, it's about this intrinsic causal structure, this A -structure.

Okay, let's try to bring this all together, though.

We started with this great divide of being between intrinsic conscious existence and extrinsic relative existence.

How does this whole IIT framework, with its axioms and postulates and CIIC, change our picture of what truly exists?

It paints a very different picture.

That great divide is the fundamental split.

When you fall into that deep dreamless sleep we talked about, or more drastically enter a coma, you cross that chasm.

Your intrinsic existence ceases.

Only the extrinsic shell remains, existing for others.

Think about early Earth.

Billions of years ago, lifeless.

Lots of physical stuff, sure.

But according to IIT, it was just ontological dust.

Systems with basically zero A.

The world was dark, phenomenally speaking.

Like, a play before empty benches, as the chapter says.

No one home.

So, that old philosophical question.

If a tree falls in the forest and no one's around?

IIT gives a clear answer.

No sound.

Sound is experience.

It requires a conscious observer, a system with sufficient college to register it.

But IIT goes even further.

It suggests that without a conscious subject making distinctions, the very concepts of tree or forest don't meaningfully exist either.

They are carved out of the formal stuff by a conscious mind.

Before consciousness, it was just, as Democritus said, atoms in the void.

Wow.

So when did consciousness, this intrinsic existence, likely first appear?

The chapter suggests the first flickering of phenomenal light probably emerged during the Cambrian explosion,

maybe 530 million years ago, when the first primitive nervous systems evolved in creatures like jellyfish or worms.

Simple nervous nets capable of some minimal level of integrated information, some tiny cane.

And from there, as brains became more complex, that phenomenal light presumably burned brighter and brighter.

This sounds a bit like panpsychism, the idea that consciousness is everywhere or fundamental to the universe.

Is IIT a form of panpsychism?

It definitely shares the intuition that consciousness is more fundamental and widespread than traditional materialism allows.

The chapter even quotes Hamlet, you know, there are more things in heaven and earth that are systems can generate a maximum of integrated information, IIO, then IIT says it feels like something to be that system, maybe just a dim feeling like basic aversion or attraction, perhaps similar to what a fetus might experience late in gestation.

But it's not saying everything is conscious.

No, and that's a key distinction.

IIT is actually much more constrained than many forms of panpsychism.

It predicts that most things, a rock, a pile of sand, your laptop, as currently built a star, do not constitute a maximum of integrated information.

Their causal power isn't integrated in the right way.

It can be broken down into simpler parts.

So they lack intrinsic existence.

They're not conscious.

It's not consciousness everywhere, only where the specific structural requirements for high AI are met.

Okay, so it's specific complex systems, not just any matter.

Are there any other maybe surprising implications of this A based view?

Well, one really intriguing possibility mentioned in the chapter is that a single physical system, like one human brain,

could potentially support multiple distinct maxima of A simultaneously.

Imagine your main conscious experience corresponds to the largest dominant A structure, but maybe there's another smaller non -overlapping network of neurons elsewhere in your brain that also forms a local maximum of A.

So two consciousnesses in one head.

Potentially,

a main one, and maybe a minor one with its own simpler, separate experience, unable to speak or control the body directly, but still existing intrinsically.

This could theoretically offer explanations for things like driving on autopilot while you're deep in conversation on the phone.

Maybe the driving actions are handled by one conscious complex while the conversation is handled by another.

Or perhaps phenomena like mind wandering, or even some dissociative states.

It's speculative, but allowed by the theory.

That's mind ending.

Okay, one last thing.

Is there like a threshold, a certain amount of it may you need to cross to suddenly become conscious.

That's a really important nuance.

IIT says no, there isn't a sharp threshold number.

It's not an on off switch.

If a system has any intrinsic cause effect power, any ill greater than zero, even if it's itsy bitsy, as the chapter puts it, then it will feel like something.

The amount of consciousness, the richness and complexity of the experience scales with ales, but the principle holds even for very small amounts.

It's a continuum.

Wow.

Okay.

That was a lot to take in, but incredibly fascinating.

We've gone from the basic question of existence to these incredibly specific ideas about causal power as structures and how they might actually be experienced.

It really does challenge you to rethink what's going on inside your own head and what it means for anything to be real.

Starting with experience itself makes a huge difference.

It really does.

And maybe that's the thought to leave our listeners with.

How does thinking about existence in terms of intrinsic causal power, in terms of change your perspective, does it shift how you view your own consciousness or the possibility of consciousness in other animals or even machines?

And what about all the stuff around us that exists only extrinsically, only for others?

It definitely gives you a new lens to look at reality.

A very powerful lens indeed.

Thank you for joining us for this deep dive today.

And thank you for listening and being part of our community.

We'll catch you next time.