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

The basic parts, the start-up molecules, can be supplied in abundance and don't have to be made by some elaborate process. That immediately makes things simpler.

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.

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

It's a lot easier to see, at least in some cases, what the long-term limits of the possible will be, because they depend on natural law. But it's much harder to see just what path we will follow in heading toward those limits.

...Local prohibitions cannot block advances in military and commercial technology... Democratic movements for local restraint can only restrain the world's democracies, not the world as a whole.

Nature draws no line between living and nonliving.