Well, I just imagined a bunch of things - a rubik's cube spinning, a piece of code I worked on today, some of my friends, a cat... There's patterns of activations of neurons in my head, which correspond to those things. Perhaps somewhere there's even an actual distorted image.
Where in the database is the image of that cat, again?
By the way there's a lot of subjectively distinct ways that can produce the above string as well. I could simply have memorized the whole paragraph, and memorized that I must say it at such date and time. That's clearly distinct from actually imagining those things.
One could picture an optimization on WBEs that would wipe out entirely the ability to mentally visualize things and perceive them, with or without an extra hack so that the WBE acts as if it did visualize it (e.g. it could instead use some CAD/CAM tool without ever producing a subjective experience of seeing an image from that tool. One could argue that this tool did mentally visualize things, yet there are different ways to integrate such tools and some involve you actually seeing the output from the tool, and some don't; absent an extra censorship hack, you would be able to tell us which one you're using; present such hack you would be unable to tell us so, but the hack may be so structured that we are very assured it doesn't alter any internal experiences but only external ones).
edit: bottom line is, we all know that different subjective experiences can produce same objective output. When you are first doing some skilful work, you feel yourself think about it, a lot. When you do it long enough, your neural networks optimize, and the outcome is basically the same, but internally, you no longer feel how you do it, it's done on instinct.
- Eliezer Yudkowsky, "Value is Fragile"
I had meant to try to write a long post for LessWrong on consciousness, but I'm getting stuck on it, partly because I'm not sure how well I know my audience here. So instead, I'm writing a short post, with my main purpose being just to informally poll the LessWrong community on one question: how sure are you that whole brain emulations would be conscious?
There's actually a fair amount of philosophical literature about issues in this vicinity; David Chalmers' paper "The Singularity: A Philosophical Analysis" has a good introduction to the debate in section 9, including some relevant terminology:
So, on the functionalist view, emulations would be conscious, while on the biological view, they would not be.
Personally, I think there are good arguments for the functionalist view, and the biological view seems problematic: "biological" is a fuzzy, high-level category that doesn't seem like it could be of any fundamental importance. So probably emulations will be conscious--but I'm not too sure of that. Consciousness confuses me a great deal, and seems to confuse other people a great deal, and because of that I'd caution against being too sure of much of anything about consciousness. I'm worried not so much that the biological view will turn out to be right, but that the truth might be some third option no one has thought of, which might or might not entail emulations are conscious.
Uncertainty about whether emulations would be conscious is potentially of great practical concern. I don't think it's much of an argument against uploading-as-life-extension; better to probably survive as an up than do nothing and die for sure. But it's worrisome if you think about the possibility, say, of an intended-to-be-Friendly AI deciding we'd all be better off if we were forcibly uploaded (or persuaded, using its superhuman intelligence, to "voluntarily" upload...) Uncertainty about whether emulations would be conscious also makes Robin Hanson's "em revolution" scenario less appealing.
For a long time, I've vaguely hoped that advances in neuroscience and cognitive science would lead to unraveling the problem of consciousness. Perhaps working on creating the first emulations would do the trick. But this is only a vague hope, I have no clear idea of how that could possibly happen. Another hope would be that if we can get all the other problems in Friendly AI right, we'll be able to trust the AI to solve consciousness for us. But with our present understanding of consciousness, can we really be sure that would be the case?
That leads me to my second question for the LessWrong community: is there anything we can do now to to get clearer on consciousness? Any way to hack away at the edges?