PZ has written a reply to my post on brain uploading. I think he gets some things definitely wrong, but in this post, I just want to make a few clarifications that I should have made in my original post:
Uploading will require significant advances in the technologies we use to study the brain. PZ’s post mentions the nematode worm, an animal that many neuroscientists study because it has such a simple nervous system. I almost mentioned the nematode worm myself in my post to illustrate this point.
I had a professor in undergrad, Tony Stretton, who had spent decades studying the nematode worm. He once told us that when they started studying it, they thought it was so simple it would be easy to completely work out how its nervous system works. They were wrong, it turned out to be much harder than that.
Based on that, I think it’s safe to say that just doing more of what we’ve been doing in neuroscience will not bring us complete, accurate computer models of the human brain in even two centuries. We’ll need better technologies for studying the brain. But that will take time, which makes me very skeptical about predictions that uploading will be here in a couple decades. (I was probably too understated about that last point in my original post.)
I don’t think uploading will necessarily be the technology that radically changes the world. As I said in my previous post, I focused on uploading because I think in some ways it’s more straightforward than the issue of AI written from scratch (de novo AI, it’s been called).
Still, it may be that de novo AI is a much better approach to building powerful AI than brain uploading is, and consequently de novo AI will be the big disruptive change that will happen first. That view is compatible with the view that brain uploading would become possible given a couple centuries of uninterrupted technological progress.
I’m apprehensive about the effects uploading and other future technologies may have on the world. On balance, technology has so far been a plus for humanity. So I don’t want to be too pessimistic about uploading and other possible future technologies. But I wouldn’t be too sure the effects will be good either.
For example, Robin Hanson has argued that uploading would mean the return of slavery and a return to virtually everybody living a subsistence existence. Hanson has also tried to argue that wouldn’t be such a bad thing, but (no surprise) others are dubious. Or: is there a risk that a copy clan (as described in Muehlhauser and Salamon’s paper) could take over the world?