What is a camera? A lens focuses light reflected from an object onto a plane to form an “image” - so what? Ah, but place an emulsion of light sensitive molecules at that plane, or perhaps an array of light-sensor circuits, and it becomes something else entirely: an image storage device. A memory of the object has been created which can be accessed even after the object itself has been destroyed. A “copy” of the object has appeared: not a literal, exact 3-D copy (like, say, that most excellent of replicators, a DNA molecule) but something else having a link to the original source which may now have been thrown on a bonfire.
Now, what is the nature of that memory? The object itself is physical - an arrangement of particles at a particular energy state (ultimately, a configuration of spacetime). The image of the object is also: a pattern of wave-photons of particular energy as they cross a 2-D plane. All of this would be the case even if no human had ever existed, and the lens was a naturally occurring piece of quartz casting an image on the walls of Plato’s cave. The object and the image are physical things.
But what of the memory of the object - the silver halide emulsion after immersion in various organic compound mixtures, or the configuration of logic gate switches in a silicon chip, which store the wavelength and the intensity of the light at each tiny point on that 2-D plane? Clearly, just as the molecule-comprising object and the incident photon-comprising image are physical things, so the developed emulsion and the logic gates are physical as well.
So far, our brief philosophical sprint doesn’t appear to have tipped any metaphysical hurdles. None of this stuff needs a human mind anywhere near it - the piece of quartz could even have cast the same image on the cave wall for so long that the image was ‘burned in’, providing an entirely natural instance of the formation of a “memory”. But to deviate even slightly from our course has us careering straight for a metaphorical, metaphysical brick wall: what about the data, the information? Surely that is not a physical thing?
Now, I am a physicalist, and so I say it is (or at least, that it “supervenes on” the physical), but we’re getting way ahead of ourselves. It is altogether far more difficult to move an abstract such as “data” from the metaphysical realm to the physical than our aforementioned object, image or memory. However, bear with me.
The permanent storage of a 2D image can be explained in solely physical terms, be it via silver halide molecules or CMOS sensors and Flash memory. Is there any other way of capturing and storing an image? Well, yes there is. Studies show that a never-before-seen image can be captured and stored literally within a fraction of a second (although that short-term memory must be ‘reinforced’ for a few seconds afterwards to transfer it to longer-term memory to stop it being lost) by a biological brain.
Of course, human (or avian, or even insect) visual sensory memory has all kinds of differences to photography (wet or digital). Indeed, the human retina performs so much ‘pre-processing’ before it sends a signal to the visual cortex that it is actually considered part of the brain even by anatomists. I have a memory of Darth Vader being as black as black can be, and yet when look at the screen I saw him on in daylight it is either mid-grey (TV) or even pale white (cinema). My retina took in that image and Photoshopped it for me, turning that grey or white into deepest black.
Clearly, I don’t store countless gigabytes of data every minute, and yet I can still remember the briefly (and never before) -seen face of the shopkeeper who sold me a newspaper yesterday: holding her in my ‘mind’s eye’, I could even reconstruct if I could manipulate a pencil accurately enough. And yet I can’t remember the front page of the newspaper in anything like the same detail, which I would if I had taken a 10 megapixel photo and transferred it to my biological hard drive.
Humans, and birds, and all kinds of other biological brains, store things in different ways to silicon brains. Faces have extremely specialised and extensive modules to process and store them, and even simple objects are stored differently. Where the silicon brain has 2-D “pixels”, the biological brain uses 3-D “voxels” (otherwise known as geons to form) what is called a two-and-a-half-dimensional sketch. Human brains (and pigeon brains) take the raw signals from the light sensitive cells in the eye and identify edges and colours, breaking down each image into recognised components. Common configurations of these components are associated in the brain with linguistic referents (“words”): a cylindrical geon with a ‘U-shape’ geon parallel to the straight edge is a “mug”: if instead the U-shape geon stretches over the circular cross-section, we’re looking at a “bucket” (see page 35 of this enormous but illustrative PDF).
However, I would not wish to get into a discussion here about the technical details of visual cognition. All I seek to explore here is the contention that our memories of objects are not fundamentally different in nature to the objects themselves. If we can agree that this is so, we can move forward to use senses and memory as the basis for an explanation of other aspects of cognition.
Having read through this OP again I have, right now in my mind’s eye, a memory of Darth Vader holding a watering can. I can see him right there, calling to Luke in Bespin City with a green plastic watering can in his left hand! But this is not a “memory” as such. I have superimposed a memory of a watering can onto a memory of Darth Vader: I have Photoshopped my visual memories into something which was never photographed: this, I propose is the basis of creativity: again I would hope you understand that I don’t consider this any kind of step away from the “physical” either. Similarly, certain visual memories may be associated with other sense information, or significant activity in the amygdala (ie. correlating with strong emotion): yet again, I would propose that this is not qualitatively different in nature.
I am not a cognitive psychologist. I’ve probably only read the same popular writers many of you have, such as Stephen Pinker, Susan Greenfield, Jerry Fodor, Daniel Dennett, Roger Penrose and the like. Anyone with any expertise could almost instantly have me on the horns of a dilemma : OK smart arse: why aren’t faces broken down into Mr Potato Head geons like watering cans? How do humans “understand” Godel’s Incompleteness Theorem, clever clogs? If my feelings are just a sum of cognitive module parts, how come I feel like it’s more than that, huh meatbrain?”
As I have said elsewhere, explaining consciousness in terms of biology and computation is the challenge of this millennium, just as Newton, Darwin and Einstein tackled other phenomena in the last. The bridge between cells and mind currently contains many gaps having a few ropes thrown tentatively across, which may well snap under pressure. But I consider that those gaps are shrinking every year, to be replaced by sturdy experimental supports, to the extent that I simply cannot see the entire bridge crumbling to nothing just because of some incredibly specific, not-quite-spanned gap.
I would ask you to approach this thread not by asking “Am I a biological computer?” but “Could I be one?”. Also, while I’ll try and answer any questions as best I can, I also reserve the right to turn it around and explore the alternatives offered by my questioners (ie. if the mind does not emerge from biology, where are you saying it does come from?). Finally (cos it’s my thread, dammit!) I’ll suggest dedicated threads for any bifurcations I think are particularly distracting, such as the contention that there are no physical things in the first place - leave them here, for example.
Don’t worry, I’m sure a right-old disagreement will crop up here sooner or later.