Tim Worstall linked to an article about Moore’s Law and I ended up writing a somewhat rambling comment. The original article pointed out that it wasn’t so much technical limitations that would prove the end of Moore’s Law, but the high cost of manufacturing improved chips. Tim mentioned that an economic limit to Moore’s law would be if the cost of more powerful chips outweighed the benefits.
Now, I probably read too much science fiction, and too much Ray Kurzweil, but I’ve got some strong ideas about what the benefits of ever increasing computing power can be. For one thing, I think artificial intelligence is possible. I think the human brain is just a mechanism and that if we can learn enough about how it works we can replicate it. With enough computing power, we can write a program that works like a human brain and is intelligent and self-aware. Now that’s got immense benefits and will surely be worth immense cost.
Just imagine what you can do. For one thing, you can set your thinking machine to the task of inventing better thinking machines. Or inventing anything else you might like. Imagine a computer that can simulate 500 engineers working on designing a new aeroplane. Imagine one that can do it 1000 times faster than real-time. In a year you could have the output of 500 engineers working for 1000 years. That’s going to be a pretty good aeroplane. Everyone will be able to have their own personally designed aeroplane. It’s a bit of a silly example, but it shows how far off the limit to desire for more computing power might be.
The ability of AI to invent better AI could lead to an explosion in progress that Kurzweil describes as a the singularity. (I know Vernor Vinge invented the term but he uses it differently, to mean a point beyond which we can make no meaningful predictions of the future. But I think Kurzweil’s singularity is more interesting because I think we can imagine what we might like the outcome to be.)
Here’s the outcome I’d like: if we don’t have the ability already, we set our computer engineers to inventing Drexlerian nanotechnology: molecular manufacturing. Then we have them design tiny robots that live in our bodies and keep us healthy. The next step is to have the tiny robots interface with our brains and create a brain-machine interface so that we can, if we choose, experience virtual reality — a simulated universe of our own design. Ultimately we might not need bodies at all. Freed from physical limitations we can enjoy infinite wealth, each person a creator of universes. We can commune with our friends in Middle Earth casting spells one day and go parachuting on Jupiter the next.
I think that would be worth a lot of money. So let’s just say I don’t forsee any limit to the desire for more computing power or what people would be willing to pay for it.
But I have one worry, which Tim Worstall’s article alerted me to. What if the next generation of computers is too expensive to be worth building? How would we get to the (next+1)th generation? To double computing power, it might cost 100 times as much, and the things you can do with double the computing power might not be worth that. It would be like a flat spot, or minima, in the cost benefit curve that we would be stuck in forever.
Has this ever happened? I can’t quite think of a technological dead-end like it, but then it would by nature be an obscure technology that few would have heard of. Space flight, for example, could conceivably suffer from this problem. It might be possible to make a fortune mining the asteroids but if no-one can make money launching rockets into space it might never happen. In reality this doesn’t seem to happen: advances in space travel slowed down for a while, but then other technologies made it cheaper and now billionaires are building space-ships with only vague ideas about how to make money from it. In other words, if people want it to happen, it happens.
So while I can imagine advances in computing slowing down a lot if the economic conditions aren’t right, I can’t imagine them stopping for good. New technology in other areas will constantly change the game. And the fact that better computing makes the invention of better computing easier must be a pretty strong impetus to progress.