Technology is not destiny. We shape our destiny.

Electricity is an example of a general purpose technology, like the steam engine before it. General purpose technologies drive most economic growth, because they unleash cascades of complementary innovations, like lightbulbs and, yes, factory redesign.

Technology has made it easier for different firms to coordinate their activities with one another, and they don't have to be part of one company. They can get the benefits of scale without the inertia of scale.

But the broader lesson of the first Industrial Revolution is more like the Indy 500 than John Henry: economic progress comes from constant innovation in which people race with machines. Human and machine collaborate together in a race to produce more, to capture markets, and to beat other teams of humans and machines.

In the global millennium goals, we're on track to beat and eliminate severe poverty. So there are lots of positive trends. I think the world in 25 years could be a much better version of the world we have today. But the role of humans would still be fundamentally at the center of that.

Because the process of innovation often relies heavily on the combining and recombining of previous innovations, the broader and deeper the pool of accessible ideas and individuals, the more opportunities there are for innovation.

It's most useful to think about not jobs but tasks. And within any given job, there are lots of different tasks. If you're a radiologist maybe reading the images machines can be able to do that better, maybe making the broader diagnosis and communicating it to the patients.