Matt Perryman

Brains don’t build pictures of the world (and you don’t know the world through a mental picture)

These internet comments that assume "brains build pictures of reality" are teaching me that Kant, Heidegger, and Wittgenstein don't get nearly enough attention in nerd culture.

By Matt Perryman

What can you gift to the Scrooge McDuck in your life who already owns everything in town?

I can’t give you something if you already own everything. Anything I give you is already yours.

Earlier this week I posted the following Note:

This scandalous thought provoked some extremely light outrage.

Could it be true? The brain doesn’t construct mental pictures of the external world, allowing us access to the great wilds of Reality?

The mental picturing theory, as I will call it, goes like this:

Our subjective awareness does not give us direct, immediate, unfettered access to Reality.

Instead, we know the external world through our sense organs, the eyes, ears, nose, tongue, and various receptors in the skin and muscles and so on.

Some cause in the external world impacts our sense organs. Light stimulates the retina, pressure stimulates the nerves in the skin, and so forth.

Once stimulated, said senses pass on the information to the mind or brain, which does some slick hand-waving stage magic that fabricates a mental picture in your mind.

Because we’re locked within our senses, that mental mini-map in our heads is our only access to the external world.

Note: Brains are physical objects. Physical objects don’t have mental properties or experiences. This is important to remember.

Sound good?

It’s totally and irrecoverably wrong.

Which came first, the cause or the world?

If brute sensations are the basic building block from which a mind or brain constructs the external world, then you’ve got yourself a problem.

Here’s the step by step breakdown.

  1. Sensations are the result of external causes stimulating the sense organs.
  2. The subject (mind/brain) constructs an internal mental picture or “map” of the external world from these millions and billions and trillions of sense impressions.
  3. The only way to know the external world is through the causes impacting the sense organs and the resulting mental picture.

∴ Therefore, the external world is a subjective mental picture constructed by the (mind/brain) out of its sensations.

Seems tidy enough. Case closed? Not so fast.

There’s a missing premise:

  • The external world includes everything in the external world.

That “everything” includes a) the causes acting on the sense organs and b) the sense organs.

From the missing premise we get the following:

  • If sensations are the result of external causes stimulating the sense organs, then both the cause of sensations and the sense organs belong to the external world.
  • By premise (2), the (mind/brain) assembles externally-caused sensations into an inner mental picture of the external world.
  • According to the epistemological condition in premise (3), the only way to know the external world is through the mental picture created from external causes impinging on the sense organs.
  • But by the missing premise, the sense organs and the external causes that stimulate them belong to the external world, and not to a mental picture created by the mind.

∴ Therefore, the external world is not a subjective mental picture constructed by the (mind/brain) out of sensations.

When an argument leads to the truth of both a statement and its contrary, you’ve got a serious problem in your reasoning.

If this silly story is right, then the mind/brain receives data from the senses, then uses that same sense-data as evidence that sense-data are fabrications of the mind/brain.

If the picture-making argument is true, the World is and is not a subjective mental picture assembled out of sensations.

The committed materialist always needs a minute to recover when the logical fault is explained.

The honest ones will stop and say, huh, that is a problem, I should rethink this.

The many shrieking lunatics playing dress-up as reasonable and scientific people on the internet will double down and turn the “Ackshually” dial to 11.

Regardless — in their quest to know the world, the materialist’s brain fetish ends up destroying it.

If everything we know is assembled by the brain out of raw sensations, there is no world to know.

But the science says…

The theory of mental picturing, which belongs with a certain family of epistemological theories, is about as old as writing.

In modern European thinking this theory, called empiricism, is at least as old as John Locke’s philosophy. Later developments through Bishop Berkeley and David Hume took it to strange places not too different from the paradox described above.

Versions of it were known in ancient Greece. This tidy quote from the Pre-Socratic fragment of Democritus sums up the paradox.

Intellect: “Color is by convention, sweet by convention, bitter by convention; in truth there are but atoms and the void.”

Senses: “Wretched mind, from us you are taking the evidence by which you would overthrow us? Your victory is your own fall.”

Data taken from the senses are liberally deployed in a total skeptical assault on data from the senses.

Yes, some version of empiricism is widely believed by many prominent figures opining about the nature of the mind, natural and artificial. But it isn’t a scientific discovery or theory account that some scientists loudly believe it. Empiricism is a set of philosophical assumptions about the nature of knowledge and rationality that some public figures dress up as The Science.

The problem is that a lot of influential people working in fields like cognitive science and artificial intelligence believe that the empiricist theory just is the theory of knowledge and rationality.

(Empiricism’s cousin, called positivism, is an even harder-core form of empiricism that was trendy among scientific philosophers in the early 20th century. Owen Barfield made some interesting remarks about the cold grip of positivism on the popular imagination.)

This logical trap that’s been known since the 5th century BC now appears in our most serious scientific theories of the mind.

A subject creating mental representations of the external world.

What’s the alternative to the mental picturing theory?

The idea that a sensation contains something of the external world, yet is already mental, is a powerful idea that once rocked philosophy to the core.

Back when we had a literate culture, every educated person knew of Immanuel Kant and his transcendental philosophy. One of Kant’s many insights held that there are no sensations without concepts and no concepts without sensations.

What we call “the external world” is already colored by the conceptual activity of thought.

The sensations “out there”, caused by a fully independent reality, are already products of subjective mental activity.

For sensations to be rational and take part in knowledge, they must be intelligible as sensations.

Otherwise, “sensations” are just meaningless causes and effects, events that just happen, rocks falling and waves crashing.

An isolated mind cannot build a picture of reality from the same stuff that makes the picture.

If you follow mainstream discussions and writings about the mind, from psychology to philosophers still obsessing over such things as “consciousness” and “qualia”, you’ll notice that much of it aims to show how a reality already divided between mental and material stuff can be brought back together.

The more interesting idea is that mind and world never were split to begin with. Subject and object are continuous. The divide between them is not in reality, but in the way we involve ourselves as subjects in the objective world.

The idea that we’re isolated brains peering out at the world through the keyhole of our physical senses can’t get off the ground.

If it’s true, then there is no world to know.

If you already own everything, I can’t give you something that isn’t yours.

Before you get out of here

If you found this article valuable, interesting, funny, or it made you upset that you had to use your mind for something besides infinite scrolling, pass it along.

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