The Black Box Brain Problem

If I found a black box with a number keypad and a printer tape, I could make tables of all the inputs I tested and the outputs.  I put in a 1 and get a 3.  A  7 gets me 127.  Non-integers return ‘ERROR.’  Depending on what ends up in my table, I might be able to make some reasonably confident guesses about what was going on inside the box.  Provided I had been careful to watch out for positive bias.  (Go ahead, read the linked article, it’s really good and I’ll be here when you get back).

This is what neuropsych is doing a lot of the time, and I’m all in favor.  But there’s a weird overreach (exacerbated by lazy science reporting) that’s happening as the discipline branches out.  There’s an idea that one you have an input-output table, the work is done, and that there’s no reason to wonder what’s actually going on inside the box.  Roger Scruton puts his finger on it in his essay “Brain Drain” for the Spectator.

It seems to me that aesthetics, criticism, musicology and law are real disciplines, but not sciences. They are not concerned with explaining some aspect of the human condition but with understanding it, according to its own internal procedures. Rebrand them as branches of neuroscience and you don’t necessarily increase knowledge: in fact you might lose it. Brain imaging won’t help you to analyse Bach’s Art of Fugue or to interpret King Lear any more than it will unravel the concept of legal responsibility or deliver a proof of Goldbach’s conjecture; it won’t help you to understand the concept of God or to evaluate the proofs for His existence, nor will it show you why justice is a virtue and cowardice a vice. And it cannot fail to encourage the superstition which says that I am not a whole human being with mental and physical powers, but merely a brain in a box.

Intuitively, we have much stronger preferences about the entries in an input-output table of our mind than we do for a similar table for any black box machine we might pick up off the street.  When it comes to other natural processes, we might find a particular input-output pair surprising, but we’d be unlikely to say it needed correction.  Describing the stimulus-response linkups is insufficient.

That’s not to say research at that level isn’t worthwhile.  It can be fodder for future (transhumanist) intervention.  It can make it easier to pin down some of the prompts that lead us astray, so we can avoid them the way an alcoholic avoids alcohol.  These kinds of applications are just the neuroscience equivalent of researching cognitive biases.

We just have to avoid being indifferent to the ways the stimuli and responses link up.  And neuroscience isn’t the discipline that will help us with the oughts — we have to take the brain scans and input-output tables back across campus to the philosophy lab.

In the example at the beginning of the post, I wouldn’t be able to figure out that my hypothetical black box was generating the nth Mersenne Prime (given n as the input) unless I was already fluent in mathematics.  Interpretation takes different skills than dissection.  Speaking only the language of biology, we can describe the brain, but we can’t say anything that interesting about cognition.

David Alpert, a quantum physicist at Columbia, makes a similar complaint in his NYT review of Laurence Krauss’s A Universe from Nothing: Why There Is Something Rather than Nothing:

It happens that ever since the scientific revolution of the 17th century, what physics has given us in the way of candidates for the fundamental laws of nature have as a general rule simply taken it for granted that there is, at the bottom of everything, some basic, elementary, eternally persisting, concrete, physical stuff. Newton, for example, took that elementary stuff to consist of material particles. And physicists at the end of the 19th century took that elementary stuff to consist of both material particles and electro­magnetic fields. And so on. And what the fundamental laws of nature are about, and all the fundamental laws of nature are about, and all there is for the fundamental laws of nature to be about, insofar as physics has ever been able to imagine, is how that elementary stuff is arranged. The fundamental laws of nature generally take the form of rules concerning which arrangements of that stuff are physically possible and which aren’t, or rules connecting the arrangements of that elementary stuff at later times to its arrangement at earlier times, or something like that. But the laws have no bearing whatsoever on questions of where the elementary stuff came from, or of why the world should have consisted of the particular elementary stuff it does, as opposed to something else, or to nothing at all.