Just before I left the States, I read this, shall we say, interesting article about how your brain is not a computer. The subhead, which does more or less summarize the content, is:
Your brain does not process information, retrieve knowledge or store memories. In short: your brain is not a computer
Curiously, in order to comprehend the article, I had to retrieve knowledge and stored memories about neuroscience (I have a degree in that) and computers (I worked in the field for several years), and I had to process the information in the article and in my background, and I found that article confusing. It did not compute.
Jeffrey Shallit, who knows much more about the information processing side of the story, also found it somewhat enraging.
The foundation of the author’s argument is that the brain does not store information in the naive way that he expects. And that’s the heart of the problem: he seems to have a crude knowledge of how modern computers implement information processing, and has decided that because our brains don’t have registers or 8-bit data storage or shuffle around photographic images of the world around us internally, the brain must not compute things or remember things. It’s a bizarre exercise. Computer scientists don’t restrict their appreciation of computation to what they learned while programming a 6502 chip, either.
We don’t store words or the rules that tell us how to manipulate them. We don’t create representations of visual stimuli, store them in a short-term memory buffer, and then transfer the representation into a long-term memory device. We don’t retrieve information or images or words from memory registers. Computers do all of these things, but organisms do not.
Computers, quite literally, process information – numbers, letters, words, formulas, images. The information first has to be encoded into a format computers can use, which means patterns of ones and zeroes (‘bits’) organised into small chunks (‘bytes’). On my computer, each byte contains 8 bits, and a certain pattern of those bits stands for the letter d, another for the letter o, and another for the letter g. Side by side, those three bytes form the word dog. One single image – say, the photograph of my cat Henry on my desktop – is represented by a very specific pattern of a million of these bytes (‘one megabyte’), surrounded by some special characters that tell the computer to expect an image, not a word.
But the core of his rejection of the information processing power of the human brain rests entirely on the fact that we don’t encode information in the way he demands we must. He uses this example:
In a classroom exercise I have conducted many times over the years, I begin by recruiting a student to draw a detailed picture of a dollar bill – ‘as detailed as possible’, I say – on the blackboard in front of the room. When the student has finished, I cover the drawing with a sheet of paper, remove a dollar bill from my wallet, tape it to the board, and ask the student to repeat the task. When he or she is done, I remove the cover from the first drawing, and the class comments on the differences.
The student does a lousy job of drawing a dollar bill, as you might expect. When they’re allowed to copy directly from the bill to the blackboard, they do a much better job of getting the details right. Therefore, the brain does not work like a computer…or more precisely, the brain does not contain a detailed, easily accessible, high resolution photograph of a dollar bill embedded in a ‘memory buffer’ somewhere that can be pulled up and suspended in the mind’s eye (a whole ‘nother complex issue; I wonder if Epstein is a dualist?). And that’s true. It’s also irrelevant unless you’re arguing that the brain is a PowerBook Pro, which we’d all agree, it isn’t.
What is the internal representation of a dollar bill in your brain? It isn’t a photograph. It’s a more complex hierarchy of associations.
For example, when I arrived in Seoul, I took my familiar American dollars and handed them over to a man in a currency exchange booth. He handed back a stack of Korean won, and what I saw I instantly recognized as paper money. It was rectangular pieces of paper with a soft foldable texture, digits printed on them, and the kind of fine-grained printed imagery that is difficult to forge, with a picture of a person on it. Money, my brain said. It meets a series of criteria I associate with currency.
But not all. It was a different color — most American money is greenish, while these were different muted shades, like blue or yellow. The denominations were very different. I didn’t recognize this guy at all.
But it’s still obviously money. My brain seems to have a more sophisticated representation of what money looks like than correspondence to a specific nationality and denomination of bill, and this more complex encoding is regarded by Epstein as an indicator that the whole metaphor of information processing is wrong. I’d really like to see how he defines IP.
Traveling also makes that we encode information even more obvious. Imagine that you’re in your home country, and you buy something at the store: “$3.40”, the clerk says. You open your wallet, you’ve got a disordered assortment of ones, fives, and tens in there, but you instantly figure out which ones to pull out. You reach into your pocket for some change; you don’t even see it, but you can tell right away that you’ve got some quarters and dimes and miscellaneous coins, by touch. It’s fast, almost thoughtless. The facility with which you can recognize quantities and multiple units ought to tell you that there is some kind of internal representation of money in your head that you use.
We take it for granted until we’re traveling abroad. Now the clerk says “3400”, and you open your wallet, and the cues are all awry. It’s money, all right, but hey, what color are the thousand won notes again? Instead of instantaneous pattern matching, one flavor of information processing, I have to scrutinize each bill and stare at the digits and count zeroes (boy, there are a lot of zeroes on Korean cash), and do a different kind of tedious information processing to figure out how much to hand over. Forget about the coins; it’s a jumble of metal disks with no associations in my head at all, and I’d have to peer carefully at each one to figure out how much its worth.
This is true in any foreign country you visit. Canada isn’t so bad for us Americans — the numbers on the bills are just like the ones on ours, and the values are roughly similar, even if the colors are weird. Australia has even funkier colors, and the texture is off — so plasticky. Europe, forget about it — paying your bill is an exercise in calculation. More than once I’ve pulled out a wad of bills and had the clerk pick out the correct amount for me.
Isn’t it obvious that we have very specific mental representations of these things in our heads? It’s just not the stupid mental photograph Epstein demands that we have in order to fit his poor mental image of what information processing is.