Meaning is in the brain, where else?

Question

Philosophy of languages discusses the two concepts of extension and intension. Since the 1960ies Putnam published a series of papers on topics like the meaning of meaning. He argues against the view that meaning exists in the brain only: “ ’meanings’ just aint’t in the head!” By the famous thought experiment of water on the twin earth he clarified his point of view, that the meaning of a term has to take into account more than just brain states.

In the meantime, neuroscience has established itself as a player in the domain of philosophy of mind. Some researchers with a strong capability in neurobiology and philosophy have presented new models of the mind; e.g. Gerhard Roth: Das Gehirn und seine Wirklichkeit. 1994 (in German).

The philosophical approach employs a constructivist epistemology. On the other hand, neuroscience emphasizes that the content of our mental processes solely results by pattern recognition and pattern processing from the net of neural activity in the brain. The brain is deaf and blind. It neither hears nor sees nor smells nor touches etc.

It is our cognitive system, which classifies the neural input as visual, auditive, olfactoric or sensual due to the brain areas where the input comes from and due to its time-related pattern. Herefrom the brain constructs a world-model with the relevant features of our environment. This world-model is permanently updated. All our perceptions refer to this model. But the model itself stays transparent. It is invisible to our conscious awareness: We perceive the inner world-model as if we had direct contact to the things from the outside world.

My thesis:

The meaning of a term is the relation between two mental structures, both of which form part of our world-model. One structure is the pattern of the term, the other is a combination of several other patterns (the intension).

In particular, all meaning is in the brain because the world-model is in the brain.

Added: What are possible objections?

Answer 1

If you are asking is the meaning in your head all in your head, then of course the answer is yes. (I'm going to leave aside the details of your formulation, because it is specific to a degree that goes beyond what can be validated with present-day neuroscience.)

But that misses the point of the twin-earth thought experiment. I don't think it's the best thought-experiment, but it's widely known, so let's go with it for now.

In brief, suppose there is a twin earth where everything is identical and functions identically at a superficial level but where H₂O is absent and there is a substance XYZ instead (which everyone there calls "water").

Now, in a sense, "water", being all in the head of both Earthlings and Twinlings (let's call them), are exactly the same thing, because they are the same thing-to-them. In particular, their mental states might be completely indistinguishable from each other, and thus we'd say that the meanings are indistinguishable.

But in another sense, they are not the same because the substances are distinguishable (though not presently to Earthlings and Twinlings) and Earthlings mean H₂O and Twinlings mean XYZ. And this is a very important sense of meaning since we have to interact with the outside world. We expect that meanings like those conveyed by "water" will attach naturally to whatever additional things we find out about water including whether it's actually H₂O or XYZ.

So after considering Putnam's argument one can accept your thesis and yet want more, which is to also have a theory of how many different brains can refer to the same (and/or different) external entities. The purely internal account makes that exquisitely difficult.

(Yes, you eventually have to get there by considering how the models built by your brain end up with an expectation of various invariants including that XYZ isn't quite what we mean by "water", but adding that extra layer of interpretation makes the logical structure harder to see.)

Answer 2

First, I would suggest that meaning is intersubjective; this gets away from the notion of Descartian subjectivity which is self-subsistent; requiring no other.

This is Lacans distinct contribution to modern European philosophy (through his notion of the Mirror, which is just his allegorical method of re-introducing this truth; the face of the mother, or father being the 'mirror' in which we see ourselves; where we resolve a Unity of Apperception at the level of subjects; not of sensations - a la Kant).

(Unger takes this further, he grounds freedom in this acceptance).

In this picture, Crusoe on his isle, alone; would not survive for twenty years to return to the life-world; but his unity as a subject would dissolve; one cannot say disrupt; as nothing has acted on him to disrupt him; unless one goes along with Sartre (in Nausea) and say pure nothingness can act in this way.

In a different tradition, say Native Americans; aloneness is not the conditions for nothingness, as such; but to enter into a different dimension of being; the spirit world (see Black Elk Speaks). A parallel here might be with Rilkes Sonnets to Orpheus:

There rose a tree! O pure transcendence!

O Orpheus sings! O tall tree in the ear!

And all was silent. Yet still in this silence

Proceeded new beginning, sign or transformation

So, we can say meaning is both in Subjects and between Subjects.

And then of course we have the very difficult question of what is the origin of Subjecivity; which pours both light and darkness on what constitutes meaning in the world.