Any powerful technology can be abused.

Scientists study physical things, then describe them; engineers describe physical things, then build them.

Today we have big, crude instruments guided by intelligent surgeons, and we have little, stupid molecules of drugs that get dumped into the body, diffuse around and interfere with things as best they can. At present, medicine is unable to heal anything.

And that because the moving parts are a million times smaller than the ones we're familiar with, they move a million times faster, just as a smaller tuning fork produces a higher pitch than a large one.

In a sense, artificial intelligence will be the ultimate tool because it will help us build all possible tools.

If you take all the factories in the world today, they could make all the parts necessary to build more factories like themselves. So, in a sense, we have a self-replicating industrial system today, but it would take a tremendous effort to copy what we already have.

My work at MIT had focused on what we could build in space once we had inexpensive space transportation and industrial facilities in orbit. And this led to various sorts of work in space development.