Chapter 9: Genuine Intersubjectivity Conditions

Welcome to Last Minute Lecture.

This free chapter overview is designed to help students review and understand key concepts.

These summaries supplement, not replace, the original textbook and may not be redistributed or resold.

For complete coverage, always consult the official text.

Welcome to The Deep Dive, the show where we take on some of the most challenging academic work out there and really try to get to the core of what it's all about.

And today we are wrestling with a question that is, well, it's just fundamental.

It's about how we connect with each other.

It really is.

It's a paradox that's been around forever in philosophy, but now it's right at the heart of cognitive science.

And the question is this,

how does an individual mind, you know, my mind, which is completely isolated inside my own head, ever truly experience or even know that other minds exist?

It's the central puzzle, isn't it?

I mean, my entire experience of the world, my consciousness, it's all realized in my brain, right?

It's internal.

So how do I ever break out of that?

How can I have an experience that I genuinely share with you?

And that word share is key.

The difference between the social world just being input, like data I process, and it being constitutive actually part of the cognitive process itself.

That's the mission of this entire deep dive.

It is.

We're looking at a really critical chapter from the Oxford Handbook of 4E Cognition, and it throws down a serious challenge to, you know, decades of research.

It really does.

The authors are basically saying that social interaction isn't just the trigger for some internal mechanism.

They're saying the interaction is the mechanism.

Which is a huge shift.

And to get there, we have to start where these conversations always start with the the philosophical problem of other minds.

Right.

So this is the classic challenge.

If I can only ever see your body, your movements, your facial expressions, what you say, how do I ever bridge that gap?

How do I know there's a conscious thinking mind in there just like mine?

And the answer that has really dominated cognitive science for a long, long time is built on this core assumption.

It's called methodological individualism.

Okay, let's unpack that because you can't understand the chapter's argument without really getting your head around what this is and why they're trying to tear it down.

Methodological individualism basically says that any social phenomenon, I don't care how complex it is, a conversation, a team sport, anything,

it has to be explained at the end of the day by only looking at the internal processes of the isolated individuals involved.

So only what's happening inside my brain and separately what's happening inside your brain.

Exactly.

The assumption is that my internal stuff, my mental representations, my calculations, is sufficient to explain my social behavior.

And your internal stuff is sufficient for yours.

So even if we're sitting here having this really dynamic conversation, the standard scientific explanation would say all the important cognitive work is happening in my head and then separately in your head.

There's no in -between.

There's no in -between.

And this leads to a really crucial distinction that the chapter hammers home.

It's the difference between something being instrumental and something being constitutive.

Okay.

So under methodological individualism, the other person, you in this case, are always just an instrumental trigger.

Right.

You're an external cause for my internal mechanisms.

Give us a quick analogy for that.

Think of a vending machine.

You put a dollar in, that's the instrumental trigger.

It's the external cause.

But all the complex stuff, verifying the coin, turning the spiral, that all happens inside the machine.

Your action started the process, but it didn't constitute the process.

So you're not part of the vending machine's mechanism.

Not at all.

And applying that to us, I see you frown.

That's the dollar going in.

That frown triggers my internal sadness detector program.

And presto, I understand you're sad.

But the actual mechanism of understanding is seen as being entirely inside my brain.

The interaction is just the occasion for the mechanism to run.

It's not part of the mechanism itself.

Exactly.

And that is the framework that this 4E and active approach is setting out to completely dismantle.

Okay.

So this commitment to the isolated individual,

this internalism, it leads us straight to the biggest paradigm in social cognition research.

It does.

It leads to theory of mind, or Tom.

Right.

And pretty much all the different flavors of Tom, whether they were running a logical theory about other people's beliefs, or were running an internal simulation of them.

They all play by the same rules.

They all respect that individual is constrained.

The explanation for how I understand you relies solely on what my isolated mind can cook up.

But what about when we do things together?

I mean, really, together.

Like two people carrying a piano or a jazz duo improvising.

That feels like a genuine we.

It does.

And the mainstream has started to acknowledge this with ideas about collective intentionality, sometimes called the we mode.

But here's the catch.

Even when they admit, okay, sure, there are these irreducibly collective modes of being, they almost always assume that this we mode is still realized when - Inside one individual's head.

Exactly.

Each person just has a very complex representation of the we plan inside their own brain.

And this is where the whole thing just goes off the rails into a conclusion that feels, as the chapter says, totally bizarre when you compare it to real life.

We have to talk about the philosopher John Searle's conclusion here because it's so stark.

He said, if this collective feeling, this we -ness is realized only in my brain, then my experience of doing something together could exist and be completely real to me, even if your presence, your cooperation was a total hallucination.

Wait,

a total hallucination?

Or even if I'm just a brain in a vat being fed sensory information.

Okay.

Let's slow down there because that is a massive claim.

If the standard view in cognitive science is compatible with the idea that you could just be a hallucination,

what does that say about the science?

It says the traditional approach is fundamentally neutral on whether other minds actually exist.

I mean, for the science to work, it's enough that your brain behaves as if there are other people.

It doesn't matter if they're real conscious beings or just very convincing robots.

It's scientifically irrelevant under that framework.

The authors call this the problematic as if assumption.

The whole cognitive architecture is built to work whether other minds are real or not.

And this is perfectly captured by Daniel Dennett's idea of the intentional stance.

Absolutely.

Dennett's view is that when you face any complex system, like a person, you adopt a strategy.

The most useful one is the intentional stance.

You just decide to treat them as if they're a rational agent.

So you figure out what beliefs and desires they should have in a situation, and then you predict what they'll do next.

Exactly.

It's a predictive tool.

It's detached.

It's about utility.

It doesn't require any genuine connection, just accurate forecasting.

And it's this detachment that really motivates the phenomenological critique.

Because, as the authors say, these conclusions that my most profound shared moment could be a It just feels utterly strange.

It's so far removed from how we actually live.

It is.

And the reason we get to this strange place, they argue, is because of this unspoken inheritance from mind -body dualism.

The idea that the mind is locked away inside the head.

And if the mind is hidden, then all I ever perceive is your body's opaque surface behavior.

Your body is just a physical object I have to figure out.

Right.

And so I have to do all this extra cognitive work, this theory of mind stuff to try and infer the hidden mental states behind the physical mask.

This is the assumption of hidden minds.

But the phenomenologists, people like Merleau -Ponty, they just pushed back on this so hard.

They did.

They said this whole hidden minds puzzle, it sounds more like a description of certain psychopathologies, like a profound sense of detachment than it does of normal everyday social life.

That makes so much sense.

When I look at you and you smile, I don't see a set of muscle contractions that I need to run through an algorithm to decode as happy.

No, you just see the happiness.

The phenomenological claim is that we have direct perceptual experience of others.

We find ourselves from the very beginning in a world that is already shared.

The distress is in the posture.

The joy is in the expression.

So we're moving from this idea that social life is a puzzle to be solved by an individual.

To the idea that we are fundamentally beings who participate in a shared reality from the get -go.

But I can hear the counter -argument now.

A traditional scientist might say, Okay, fine.

It feels direct.

But that's just because your brain is doing the calculations really, really fast below the level of consciousness.

Exactly.

That's the wall we have to get over.

It's not enough to say it feels direct.

We have to show that the other person is actually constitutively involved in creating the social experience itself.

Okay.

So that brings us to the alternative.

If we throw out the internalist view, we have to replace it with something.

Let's define this concept of genuine intersubjectivity.

Genuine intersubjectivity is about those moments of connection where the other person, as a person, plays a constitutive role.

They're not just an input.

They're part of the machinery of the social event.

So it's not I -mode processing in it.

It's not even a simple I -U action -reaction.

It's about an emergent we,

a second -person perspective.

And the really radical claim is that you don't need all this complicated, high -level belief -desire psychology to get there.

For a lot of fundamental interactions,

just mutually engaging in embodied practices is enough.

Our movements, our gestures, our shared gaze, that's sufficient for understanding to emerge.

The understanding is in the coupling.

It's in the coupling.

And the key to that coupling is reciprocity, that constant mutual active back and forth.

To make this less abstract, the chapter gives a fantastic model of emotional interaction using this idea of the extended body.

Okay, let's walk through that.

The example is a hostile interaction.

One person is angry.

The other is shocked.

All right.

So person A is angry.

That anger isn't just an abstract thought.

It's a felt, bodily experience.

Muscle tension, a sharp tone of voice.

That's what the chapter calls intra -bodily resonance.

Inside the body.

And then that state is expressed outwardly.

Person B sees the rigid posture.

Here's the sharp voice.

And that perception doesn't just get filed away as data.

It triggers a corresponding or complementary feeling in person B.

A sense of tension, a sharp intake of breath, a feeling of withdrawal.

This is intra -bodily resonance.

Between the bodies.

Exactly.

And here's the loop.

B's reaction, the wide eyes, the tension, is immediately perceived by A.

And that changes A's internal state.

Maybe A sees B's tension as defiance, which makes A even angrier.

A's expression gets sharper, and the whole cycle just escalates.

So they're no longer two independent systems.

They're locked in this escalating dynamic.

They are.

Their bodies become a single autonomous dynamic system.

They're affecting each other in real time.

The authors call this mutual incorporation.

So my lived body is being extended by your dynamics, and yours is being extended by mine.

We're not two isolated systems anymore.

For that moment, we form an extended body.

And the experience isn't I am calculating that he is angry.

The experience is we are trapped in a tense argument.

The understanding of the tension is realized between us.

Okay, that makes sense.

But I have to play devil's advocate.

Couldn't a skeptic just say fine, that's a very complex feedback loop, but it's still just inputs and outputs being processed very quickly inside each brain.

Why is it really constitutive?

That's the million dollar question.

And the pushback is this.

Sure, you could theoretically imagine a supercomputer powerful enough to simulate that entire dynamic internally.

But why would evolution build that?

Why duplicate a complex process inside the head when the complexity is already there for free in the situation itself?

And it's a core 4E principle.

If the brain can offload some of its cognitive work onto the environment, and the other person is part of that environment, it's almost certainly going to.

It's just more efficient to participate in the dynamic than to internally compute it.

This brings us right to the mirror neuron system, doesn't it?

Because that's often held up as the biological proof of direct social understanding.

It is, and it's a good starting point.

Mirror neurons are great because they fire both when I do an action and when I see you do the same action.

So they have this built -in self other neutrality.

But the chatter argues that this neutrality is actually a big problem for explaining genuine interaction.

Exactly.

Because genuine interaction requires two things that mirror neurons on their own don't give you.

First, you need to maintain a sense of self and other.

We don't literally merge.

And second, you need reciprocity.

Oh, my mirror neurons will fire just as well if I'm passively watching a YouTube video of someone juggling.

Precisely.

They don't require that active co -regulating circular dance that we saw in the extended body example.

So M &S is maybe a foundation for simulating others, but it's not enough for constitutive interaction.

So the real goal here is to shift our perspective, to stop seeing the detached third -person theory of mind as the primary way we understand people.

And to see it for what it is.

A backup strategy.

A derivative mode we use when direct interaction breaks down or when we're reflecting on something later.

The primary social capacity is this embodied reciprocal dance.

The other person isn't just an input.

They are, as Merleau -Ponty said, the completion of a larger integrated system.

OK, if we're going to build a science on this, we need a new framework.

And that's where the inactive research program comes in.

Right.

The inactive approach is perfect for this because its central principle is that interaction dynamics can be constitutive of cognition.

It's in its DNA.

The chapter uses Francisco Varela's projected history of cognitive science to show this shift in thinking about the other.

Yeah, it's a really useful way to frame it.

He saw it in stages.

The first stage, classical cognitive science computationalism, saw the other person as just a problem to be solved, a complex object in the environment.

Then we move to the intermediate stage, which is basically where mainstream science is now.

Here, the other is an affordance.

An affordance, right.

Their existence is a given, but the scientific job is still to figure out how two independent minds build informational links between them.

It's like networking two computers.

But the future stage, the one Varela was aiming for, is the science of inner being.

Exactly.

And here, the other person and I are seen as common ground, a joint tissue.

The interaction itself co -creates a shared awareness.

We finally get to that radical idea of the other being the completion of the system.

It's a compelling vision, but it's a massive shift.

So how do we actually do this science?

The chapter lays out a methodology with three pillars.

Right.

Pillar one is phenomenology.

This is where we get our raw material.

Careful descriptions of what social experiences are actually like, empathy, direct perception, that feeling of our bodies being in sync.

Pillar two is theory.

This is the inactive approach, building concepts like participatory sense -making, the extended body, mutual incorporation.

This is the conceptual toolkit.

And then there's pillar three, experiment.

And this, the chapter says, is the big missing link.

But I mean, there are tons of two -person experiments now with hyperscanning and all that.

There are, but there's a disconnect.

Very few of them are actually designed to test for genuine intersubjectivity by integrating the first two pillars.

Worse, a lot of them, even when they find amazing interpersonal coupling, are still interpreted through the old lens of methodological individualism.

The bias is baked into the analysis.

It is.

If your only explanatory tool is it must happen in the head, then any evidence to the contrary just becomes invisible.

It's inconceivable.

To break out of that, we need a new language, a formal language.

And that language is dynamical systems theory or DST.

Precisely.

DST is the proof of concept.

It's a non -representational formal language, which means we don't have to talk about abstract symbols in the head.

It can describe the activity of neurons, bodies, and the environment all in the same mathematical framework.

So it avoids all those messy, unprovable assumptions about a cognitive unconscious where all the magic happens.

It grounds the explanation in the concrete dynamics of the situation.

And most importantly, it lets us redefine the system we're studying.

From a DST perspective, social interaction is a property of the whole irreducible brain -body, environment -body -brain system.

The entire loop is the unit of analysis.

The entire loop.

And that's how we get to say that interaction is constitutive.

The behavior of one agent depends fundamentally on its coupling with all the other parts of the system, including the other agent.

The brain isn't representing the dance, it's participating in the dance.

Okay, so with DST as our tool, we can finally look at some empirical evidence, starting with some very simple simulated agents.

Right.

We need to show that this is not just a philosophical possibility, but a technical one.

We're looking at an agent -based model from Frouz and Fouche.

And this setup is about as minimal as you can get, right?

Oh, completely.

You have two agents in a 1D world.

They can only move left or right.

Their brain is just three interconnected artificial neurons.

And their only perception of each other is a binary touch sensor.

It's either on or off F.

So they're basically little digital bumper cars.

And their task was just to learn how to coordinate,

to find each other and move together.

Exactly.

They evolved to do this.

And the first thing the researchers did was look at them in isolation.

Right, the isolated dynamics.

When an agent is alone and its touch sensor is just stuck on, on or off F, its internal neural activity always settles down into a stable state, a fixed point attractor.

It's like it gets into a predictable rut.

The input just triggers which rut it falls into.

Which is exactly what methodological individualism would predict.

The input is just an instrumental trigger.

But what happened when they were in a live interaction?

This is the crucial finding.

When they are co -regulating, bumping into each other, pushing and pulling, their neural activity never settles into those stable ruts.

Instead, their internal dynamics are maintained in these highly unstable, constantly changing states called far from equilibrium transients.

Okay, that sounds technical.

What does that mean in plain English?

It means the system is only stable because it's constantly dynamically unstable.

Think about juggling.

The pattern is stable, but the individual balls are always in motion, always on the verge of falling.

The stability is in the relationship, in the dynamic itself, not in the state of any one component.

And this unstable dynamic state is what allows them to do more complex things, like moving together in one direction.

Exactly.

The interaction itself reorganizes their internal neural dynamics, allowing them to achieve a level of coordinated behavior that neither could produce on its own.

The other agent literally becomes the completion of the system.

And the final nail in the coffin for the individualist view here is the playback condition.

Right.

They took one agent away and replaced it with a perfect recording of its movements.

So the remaining active agent gets the exact same sensory input.

But loses the ability to influence that input.

The reciprocity is gone.

It's gone.

And the moment it's gone, the complex transient neural dynamics in the active agent spontaneously break down.

The coordination collapses.

It failed because the relationship broke, not because the input changed.

Precisely.

This is the formal proof that an extended constitutive social mechanism is possible in principle.

And that opens the door to testing this in actual humans.

Which brings us to the perceptual crossing experiments.

This is such a clever way to distill social interaction down to its bare essence.

It is.

The setup is genius.

Two people separated by a wall, each controlling an avatar in a 1D space with a track ball.

The only feedback they get is a vibration in their hand when their avatar touches something.

And in this simple world, they can bump into a few things.

A static object, the other player's avatar, and this is the key part, a shadow object.

The shadow is the perfect control.

It's a perfect recording of the other player's movements, just offset in space.

So it moves in a complex human -like way, but it's not responsive.

It's not reciprocal.

And the task is simple.

Just click a button when you think you're touching the other real person.

And the original findings from 2009 were, well, they were ambiguous.

People were good at clicking on moving things, but crucially, they could not reliably distinguish between the real reciprocal avatar and the non -reciprocal shadow.

Wait a minute.

If they couldn't tell the difference, doesn't that support the old view that they're just sensitive to the input, not the reciprocity?

It seemed to at first, but a deeper analysis showed something interesting.

Objectively, they were more correct when they clicked on the real person.

And that's because when two people really interact, they tend to create these little pockets of stability.

They linger together.

So they clicked correctly more often by chance, just because they spent more time together.

So the interaction was enabling the correct answer, but it wasn't constituting their experience of the other person.

They didn't feel the who.

They just knew the where.

Which led to the critical follow -up study,

the co -regulation variation.

And the change they made was so simple, but so profound.

It was.

They just gave the participants pro -social instructions.

They said, you're a team.

Help each other out.

Your score is a joint score.

They primed them to adopt a we perspective.

And what happened?

Everything changed.

Result one,

participants were now significantly more likely to click on the other's avatar than on the shadow.

They could now successfully tell the difference.

The reciprocity became experientially real.

That's the proof right there.

The social framing, the co -regulation, it literally changed their cognitive capacity.

It did.

And result two confirmed this with their subjective reports.

When they had a successful joint click, they also reported a significantly clearer experience of the other person's presence.

So the objective behavior and this objective feeling of connection were completely intertwined through the interaction dynamic.

Completely.

And finally, result three showed that these successful clicks were preceded by an increase in co -regulated behavior, specifically turn taking, which is a behavior that can only exist in a coupled interdependent system.

And there was that fascinating detail about the timing that successful joint clicks often happened within about two seconds of each other.

Which is so intriguing.

Because it hints at this possibility of a large scale interbrain integration where the cognitive act of recognizing the other person isn't happening in one brain or the other, but is distributed across the whole coupled system in real time.

So if we pull all of this together, the philosophy, the theory, the models, the human experiments, the conclusion feels incredibly solid.

It is.

The conclusion is that co -regulated social interaction constitutes genuine intersubjectivity.

It's not a fringe theory anymore.

It's something we can never and demonstrate.

And it confirms our basic intuition that other people fundamentally shape who we are and how we think.

And it allows us to finally move beyond the constraints of methodological individualism.

We can now scientifically study mechanisms that are not just located inside an individual's head.

We can.

And when we do that, those old philosophical puzzles like Searle's brain in a vat problem, they start to lose their power.

Because the brain in a vat is, by definition, not in a reciprocal embodied interaction.

Exactly.

It is literally insufficient to generate this kind of social understanding.

The capacity requires the real physical active participation of another person.

It's not a bug.

It's a feature.

So we're moving from a science of independent information processors to a science of interdependent means.

We are.

We're finally building a cognitive science that aligns with the reality of living in a shared social world where the other person is a necessary verifiable part of our own cognition.

That was an absolutely fascinating journey from the deepest philosophical paradoxes right up to cutting edge empirical work.

We started with this idea that social life could be a complete illusion.

And we ended with scientific proof from agent models to human experiments that genuine connection is not only possible but is constituted through our embodied co -regulated interactions.

The success of that perceptual crossing study just by changing the instructions to you're a team, really says it all.

Our ability to understand each other is woven into our willingness to participate in each other's lives.

It really is.

The we is more than just the sum of an I and a U.

So as we wrap up, I'm going to leave you with one final thought to take with you.

If our ability to do something is basic as recognizing another person in a simple one D line only truly emerges when we actively co -regulate our actions.

What does that imply about the staggering complexity and interdependence that is happening right now in this very moment and all of your everyday fully embodied encounters?

Something to think about.

Thanks for diving deep with us.

We'll see you next time on the deep dive.