The Predictive Mind | Jakob Hohwy: You don't see the world
It's a brain hallucination
Try a small experiment
Close your eyes for five seconds
Then open them
You think you open your eyes
And see the room
The sky outside
The phone screen in front of you
But you don't
Your brain
From birth until now
Has never seen light for a single second
Nor heard a sound for a single second
It's sealed in the skull, a lightproof
And nearly soundproof black box
Living a lifetime in darkness and silence
All it receives
Is a stream of pulses from the optic nerve
And pulses from the cochlea
They are all the same thing
Neurons firing
There is no red in these pulses
No mother's voice
No sky outside
Just a bunch of unlabeled electrical signals
Like bitstreams in undersea cables
So how do you see sky and hear sound
Your brain isn't perceiving the world
In total darkness
It's playing a massive
Unsung guessing game with these pulses
It's guessing what these signals
Most likely mean is happening outside
Every image you've ever seen
Every sound heard, every texture felt
Is essentially guessed by your brain
This concept
In 2013
Australian philosopher Jakob Hohwy
In his book "The Predictive Mind"
Explained it systematically
In the decade since publication
It revolutionized cognitive science and philosophy
Even how psychiatry views perception
When I first finished this book
One thought kept lingering
Isn't this exactly what
The Buddha said 2,500 years ago
After 49 days under the Bodhi tree
Hello
Hi everyone
I'm Wang Lijie
In today's episode
I want you to join me
in exploring a chilling comparison
A modern Australian philosopher's
brain model built on math and neuroscience
vs. ancient Indian practitioners'
Yogacara model built on introspection
Are they talking about the same thing?
First, who is Hohwy?
Jakob Hohwy
Philosophy professor at Monash University
He's not an experimental neuroscientist
But he works with many scientists and doctors
He has a rare talent
To take clues from math, science, and philosophy
And use a framework for laypeople
To integrate them into one map
What he did
Wasn't invented from scratch
The pillars of Predictive Processing
Were built bit by bit by his predecessors
In 1999
Rao and Ballard wrote a famous paper
Proposing the visual cortex's hierarchy
Is a loop of prediction and error
Around 2005
Karl Friston of UCL
Took this even further
He proposed the Free Energy Principle
Arguing all living organisms
From bacteria to humans
Are essentially doing the same thing
Minimizing prediction error
Hohwy's contribution
Was taking these scattered academic ideas
And integrating them into a philosophy
That non-experts can understand
In "The Predictive Mind"
He wrote a bold line on page one
He said
This single mechanism
Explains perception, action
And every mental phenomenon in between
It's not a modest claim
But he has the confidence to say it
Because in his book
This mechanism truly grows into a tree
A tree explaining all mental phenomena
So how does this mechanism work?
Just remember three things
First
Your brain
In every moment
Is making outward predictions
Not conscious guesses like "it might rain"
But deep, subconscious inference
Based on existing internal models
Past experiences and genetics
Visual patterns learned in infancy
Every millisecond
Predicting the next sensory input
Second
Predictions flow top-down
Higher levels form a hypothesis
Sending it as a prediction signal
Down to lower-level regions
Lower levels compare it to actual pulses
Matching parts
Are ignored by the brain
Assumed to be correct
No processing needed
Only the mismatches
Called prediction errors
Are sent back up
To update the high-level hypothesis
Third
And most importantly
What decides the outcome
Is not truth
But precision
If your prior is strong and stable
Input will hardly change you
You see what you expect to see
Even if it isn't there
Conversely
If priors are weak and input is strong
The input leads you
Even if that input is noise
This sounds abstract
But it explains many familiar mysteries
Like the blind spot
Part of your retina lacks photoreceptors
Where the optic nerve exits
Logically
There should be a permanent black hole
But you never see it
Why?
Because at that spot, your brain
based on the surrounding images
guesses the most likely content
and seamlessly fills it in
You've looked at this brain-painted patch your whole life
without ever noticing it
Take the inverted goggles experiment
In 1896
American psychologist George Stratton
wore lenses that flipped his vision upside down
For the first few days, he couldn't walk
The whole world was inverted
But after about eight days
his brain recalibrated its predictive model
The world flipped upright again
He could live normally
When he took the lenses off
the real world appeared upside down
It took days to flip it back
The lenses were physical
but what corrected the image
wasn't the lenses
It was the predictive model quietly rewriting itself
Or consider the rubber hand illusion
In 1998
psychologists Botvinick and Cohen
published in the journal Nature
an experiment now repeatedly verified
Hide one of your hands under a table
Place a rubber hand on the table
roughly where your real hand would be
The experimenter brushes both hands simultaneously
You watch the rubber hand being brushed
After a minute or two
you get a powerful illusion
That rubber hand
becomes your own hand
Your brain has claimed it
This is predictive processing at work
Based on synced sight and touch
your brain generates the best-fit guess
And that guess is
this rubber hand is part of my body
Once that guess emerges
it becomes your reality
Then there are hallucinations
Traditional psychiatry couldn't fully explain
why schizophrenics see things that aren't there
or hear non-existent voices
In the predictive processing framework
This has become very clear
Their problem isn't seeing things that don't exist
But a flaw in their prediction mechanism
Either high-level priors are weighted too heavily
Causing predictions to override sensory input
Or low-level sensory precision is unstable
Forcing the brain to fill gaps with priors
In simpler terms
Hallucination isn't seeing extra things
It's the brain trusting its guesses too much
Now that you understand the framework of predictive processing
I want you to take a turn
Back 2,500 years
About 900 years after the Buddha's passing
There were two brothers in India
The elder, Asanga
The younger, Vasubandhu
They organized centuries of Yogacara observations
Into a single system
Today we call it Yogacara or Consciousness-Only
The core of this school
Is the Eight Consciousnesses model
It says
You think you're perceiving an objective world
But everything you experience
Is the coordination of eight types of consciousness
At the surface
Are the first five consciousnesses
Eye, ear, nose, tongue, and body
Corresponding to sight, sound, smell, taste, and touch
One layer deeper
Is the sixth consciousness
Called Mano-vijnana or mental consciousness
It assembles fragments from the first five
Into an understandable picture
Responsible for thinking, judging, and memory
Deeper still
Is the seventh consciousness
Called Manas
It has only one job
To constantly grasp onto something
And treat it as 'Self'
It's the function that makes you feel 'I' am here seeing
And 'I' am here hearing
At the very bottom
Is the eighth consciousness
The Alaya-vijnana or storehouse consciousness
It is a reservoir
Storing imprints of all past experiences
Called 'seeds' in Buddhism
These seeds
constantly affect what you see, hear, and think
When seeds meet the right conditions
they manifest
becoming your current experience
And your current experience
plants new seeds back into the Alaya-vijnana
Do you see it?
Alaya-vijnana
is that deepest a priori storehouse
What it stores
isn't clear memories you recall
but the underlying patterns of how you guess
underlying tendencies
Manas-vijnana
is the ego-centric anchor of the prediction model
All predictions
are built with the self as the coordinate
It is the mechanism that closes the loop
making the world revolve around a center
The sixth consciousness
is the reasoning layer
where prediction errors update the hypothesis
The first five consciousnesses
are not pure inputs
they arrive already carrying predictions
Every red you see, every sound you hear
is a finished product guessed and labeled
I'm not forcing a connection
This is a model from 2,500 years ago
and a model from 2013
describing the same structure
with frameworks built in the same place
Yogacara has an even sharper concept
called the Three Natures
The first is Parikalpita
It says
your predictions
completely override actual input
You no longer see the thing itself
but the story you project onto it
This matches Hohwy's extreme case
where priors overwhelm sensory input
All attachments and prejudices
all "I already knew you were like this"
are Parikalpita
The second is Paratantra
It says
nothing exists in isolation
Everything you experience
All are results of countless causes co-creating
The cup you see
Is light, the eye, the optic nerve, the cortex
The moment you learned the concept of "cup"
And the direction of your current attention
All working together
This corresponds to
The entire predictive processing
The world is never just "seen"
It is co-generated by prediction and input
The third is Parinispanna
It means
When you are no longer fooled by illusions
Nor treat dependent origins as solid things
But see that seeing itself is prediction
In that moment, what you see
Is ultimate reality
These three terms
Yogacara scholars debated for a millennium
Hohwy didn't use these words
But in the last chapter of The Predictive Mind
He said
Predictive processing shows us
The link between mind and world
Is fragile and indirect
He used "fragile" and "indirect"
To describe the same thing
Moving forward
In Hohwy's framework
He integrated another concept
Invented by Karl Friston
Called active inference
The predictive processing you just learned
Is only half the story
The other half is
The brain doesn't just wait for signals
It also actively changes the world
To make the world fit its predictions
You are hungry
Your brain predicts you shouldn't be
To fulfill that prediction
You can modify the prediction
By accepting the fact that you are hungry
Or you can modify the world
By getting up to find food
The act of eating
Is not just because you want to
But because it reduces prediction error
It sounds strange
But the meaning is profound
It says that
all your actions
from breathing
to speaking
to choosing a job
to ending a relationship
share the same underlying goal
closing the gap between prediction and reality
Your priors shape your actions
Your actions shape the next moment
The world then reinforces or loosens your priors
This cycle
has a 2,000-year-old Buddhist name
Karma
Seeds manifesting
Manifestations perfuming seeds
Seeds in the Alaya-vijnana become your experience
Your experience sows seeds back into the Alaya
This is not a metaphor
It is active inference at the conscious level
You don't live in an external world
and then feel it
You are within your predictions
carving the world into its current form
while being carved in return
into who you are now
So the real question is
if everything is driven by prediction
then what is awakening
exactly
What happens
during sudden enlightenment
This question
Hohwy didn't answer directly in his book
But his students and collaborators
in the decade following
pushed this question to a clear position
In 2020
a team led by Laukkonen
published a key paper in
Neuroscience & Biobehavioral Reviews
titled "From Many to None"
What they said
was very direct
Meditation
especially the deconstructive kind
its entire mechanism
is a systematic reduction of prediction
Focused attention meditation
like focusing on the breath
What it does
is take the brain's scattered predictions
and force them into a single point
It makes you realize
you can't stop thoughts from arising
Open monitoring meditation
like observing thoughts without judgment
What it does
is let you observe prediction itself
The background guessing process
is pulled into the foreground
You begin to see
that this emotion is a prediction
that the sense of 'self' is a prediction
even the 'external world' is a prediction
At the deepest level
is non-dual meditation
What it does
is even more radical
It makes all your predictions
temporarily lose their precision weight
In that moment, you experience
not emptiness
but everything you usually cling to
suddenly becoming
optional or different
In Hohwy's language
this is a massive prior weight reset
In Yogacara language
it is turning consciousness into wisdom
The 6th consciousness is seen through
The 7th consciousness's ego loosens
Seeds in the Alaya consciousness
lose their original precision weight
Do you know in Buddhist sutras
at the moment of enlightenment
what the most common metaphor is
Waking from a dream
Not seeing something better
Not gaining anything
Not going anywhere
Waking from a dream
You were in a dream of your own making
You took this dream as reality
Then at some point
for some unknown reason
you suddenly realize
Oh
this is a dream
It's not that the world changed
Your relationship with the world has changed
You are still looking
Still listening
Still walking
But the sense of "this is real" that locks everything in
Has loosened
Hohwy says at the end of his book
Predictive processing shows us
The relationship between mind and world
Is fragile and indirect
Indirect
These three words
The ancients had a simpler way to say it
They called it
Like a dream
I've finished the part I most wanted to share
But I want to end on a question
Without a conclusion
Hohwy didn't know about Yogacara
Asanga and Vasubandhu didn't know Bayesian inference
Between these two models
Neither needs validation from the other
Independently
Using their own tools
One with equations and neuroimaging
One with inward meditation
They reached the same place
But the reason I'm here talking about this
Isn't their similarity
But the empty space between them
Hohwy gave us a microscope
To see clearly how prediction works
Yogacara gave us a map inside the microscope
To show it can be seen and released personally
The microscope and the map
Are not the scenery
So finally, I leave this question to you
If everything you see right now
Is your prediction
The one who is predicting
Who is it
No need to rush the answer
Just let it sit for minutes, hours, or days
Even weeks
You will find
It won't leave
And it won't let you go
Have you read "The Predictive Mind"
What do you think
Between predicting and being predicted
What else is hidden
If you want to hear about Hovey's latest consciousness experiments
Or the part of Yogacara that deconstructs active inference
Let me know in the comments
I'm Wang Lijie
See you next time