The Crux

by rsbakker

Aphorism of the Day: Give me an eye blind enough, and I will transform guttering candles into exploding stars.

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The Blind Brain Theory turns on the following four basic claims:

1) Cognition is heuristic all the way down.

2) Metacognition is continuous with cognition.

3) Metacognitive intuitions are the artifact of severe informatic and heuristic constraints. Metacognitive accuracy is impossible.

4) Metacognitive intuitions only loosely constrain neural fact. There are far more ways for neural facts to contradict our metacognitive intuitions than otherwise.

A good friend of mine, Dan Mellamphy, has agreed to go through a number of the posts from the past eighteen months with an eye to pulling them together into a book of some kind. I’m actually thinking of calling it Through the Brain Darkly: because of Neuropath, because the blog is called Three Pound Brain, and because of my apparent inability to abandon the tedious metaphorics of neural blindness. Either way, I thought boiling BBT down to its central commitments would be worthwhile exercise. Like a picture taken on a rare, good hair day…

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1) Cognition is heuristic all the way down.

I take this claim to be trivial. Heuristics are problem-solving mechanisms that minimize computational costs via the neglect of extraneous or inaccessible information. The human brain is itself a compound heuristic device, one possessing a plurality of cognitive tools (innate and learned component heuristics) adapted to a broad but finite range of environmental problems. The human brain, therefore, possesses a ‘compound problem ecology’ consisting of the range of those problems primarily responsible for driving its evolution, whatever they may be. Component heuristics likewise possess problem ecologies, or ‘scopes of application.’

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2) Metacognition is continuous with cognition.

I also take this claim to be trivial. The most pervasive problem (or reproductive obstacle) faced by the human brain is the inverse problem. Inverse problems involve deriving effective information (ie., mass and trajectory) from some unknown, distal phenomenon (ie., a falling tree) via proximal information (ie., retinal stimuli) possessing systematic causal relations (ie., reflected light) to that phenomenon. Hearing, for instance, requires deriving distal causal structures, an approaching car, say, on the basis of proximal effects, the cochlear signals triggered by the sound emitted from the car. Numerous detection technologies (sonar, radar, fMRI, and so on) operate on this very principle, determining the properties of unknown objects from the properties of some signal connected to them.

The brain can mechanically engage its environment because it is mechanically embedded in its environment–because it is, quite literally, just more environment. The brain is that part of the environment that models/exploits the rest of the environment. Thus the crucial distinction between those medial environmental components involved in modelling/enacting (sensory media, neural mechanisms) and those lateral environmental components modelled. And thus, medial neglect, the general blindness of the human brain to its own structure and function, and its corollary, lateral sensitivity, the general responsiveness of the brain to the structure and function of its external environments–or in other words, the primary problem ecology of the heuristic brain.

Medial neglect and lateral sensitivity speak to a profound connection between ignorance and knowledge, how sensitivity to distal, lateral complexities necessitates insensitivity to proximal, medial complexities. Modelling environments necessarily exacts what might be called an ‘autoepistemic toll’ on the systems responsible. The greater the lateral fidelity, the more sophisticated the mechanisms, the greater the surplus of ‘blind,’ or medial, complexity. The brain, you could say, is an organ that transforms ‘risky complexity’ into ‘safe complexity,’ that solves distal unknowns that kill by accumulating proximal unknowns (neural mechanisms) that must be fed.

The parsing of the environment into medial and lateral components represents more a twist than a scission: the environment remains one environment. Information pertaining to brain function is environmental information, which is to say, information pertinent to the solution of potential environmental problems. Thus metacognition, heuristics that access information pertaining to the brain’s own operations.

Since metacognition is continuous with cognition, another part of the environment engaged in problem solving the environment, it amounts to the adaptation of neural mechanisms sensitive in effective ways to other neural mechanisms in the brain. The brain, in other words, poses an inverse problem for itself.

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3) Metacognitive intuitions are the artifact of severe informatic and heuristic constraints. Metacognitive accuracy is impossible.

This claim, which is far more controversial than those above, directly follows from the continuity of metacognition and cognition–from the fact that the brain itself constitutes an inverse problem. This is because, as an inverse problem, the brain is quite clearly insoluble. Two considerations in particular make this clear:

1) Target complexity: The human brain is the most complicated mechanism known. Even as an external environmental problem, it has taken science centuries to accumulate the techniques, information, and technology required to merely begin the process of providing any comprehensive mechanistic explanation.

2) Target complicity: The continuity of metacognition and cognition allows us to see that the structural entanglement of metacognitive neural mechanisms with the neural mechanisms tracked, far from providing any cognitive advantage, thoroughly complicates the ability of the former to derive high-dimensional information from the latter. One might analogize the dilemma in terms of two biologists studying bonobos, the one by observing them in their natural habitat, the other by being sewn into a burlap sack with one. Relational distance and variability provide the biologist-in-the-habitat quantities and kinds (dimensions) of information simply not available to the biologist-in-the-sack. Perhaps more importantly, they allow the former to cognize the bonobos without the complication of observer effects. Neural mechanisms sensitive to other neural mechanisms* access information via dedicated, as opposed to variable, channels, and as such are entirely ‘captive’: they cannot pursue the kinds of active environmental engagement that permit the kind of high-dimensional tracking/modelling characteristic of cognition proper.

Target complexity and complicity mean that metacognition is almost certainly restricted to partial, low-dimensional information. There is quite literally no way for the brain to cognize itself as a brain–which is to say, accurately. Thus the mind-body problem. And thus a good number of the perennial problems that have plagued philosophy of mind and philosophy more generally (which can be parsimoniously explained away as different consequences of informatic privation). Heuristic problem-solving does not require the high-dimensional fidelity that characterizes our sensory experience of the world, as simpler life forms show. The metacognitive capacities of the human brain turn on effective information, scraps gleaned via adventitious mutations that historically provided some indeterminate reproductive advantage in some indeterminate context. It confuses these scraps for wholes–suffers the cognitive illusion of sufficiency–simply because it has no way of cognizing its informatic straits as such. Because of this, it perpetually mistakes what could be peripheral fragments in neurofunctional terms, for the entirety and the crux.

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4) Metacognitive intuitions only loosely constrain neural fact. There are far more ways for neural facts to contradict our metacognitive intuitions than otherwise.

Given the above, the degree to which the mind is dissimilar to the brain is the degree to which deliberative metacognition is simply mistaken. The futility of philosophy is no accident on this account. When we ‘reflect upon’ conscious cognition or experience, we are accessing low-dimensional information adapted to metacognitive heuristics adapted to narrow problem ecologies faced by our preliterate–prephilosophical–ancestors. Thanks to medial neglect, we are utterly blind to the actual neurofunctional context of the information expressed in experience. Likewise, we have no intuitive inkling of the metacognitive apparatuses at work, no idea whether they are many as opposed to one, let alone whether they are at all applicable to the problem they have been tasked to solve. Unless, that is, the task requires accuracy–getting some theoretical metacognitive account of mind or meaning or morality or phenomenology right–in which case we have good grounds (all our manifest intuitions to the contrary) to assume that such theoretical problem ecologies are hopelessly out of reach.

Experience, the very sum of significance, is a kind of cartoon that we are. Metacognition assumes the mythical accuracy (as opposed to the situation-specific efficacy) of the cartoon simply because that cartoon is all there is, all there ever has been. It assumes sufficiency because, in other words, cognizing its myriad limits and insufficiencies requires access to information that simply does not exist for metacognition.

The metacognitive illusion of sufficiency means that the dissociation between our metacognitive intuition of function and actual neural function can be near complete, that memory need not be veridical, the feeling of willing need not be efficacious, self-identity need not be a ‘condition of possibility,’ and so on, and so on. It means, in other words, that what we call ‘experience’ can be subreptive through and through, and still seem the very foundation of the possibility of knowledge.

It means that, all things being equal, the thoroughgoing neuroscientific overthrow our manifest self-understanding is far, far more likely than even its marginal confirmation.