Biology and Self-Repair

I've been traveling like crazy, then hosting visitors, and now am laid up with a nasty cold. So not much energy for blogging. On the other hand -- plenty of time for non-expert reflections on the nature of microscopic complex systems! The thing is, I'm pretty sure that my body will eventually overcome this cold virus. That's one of the great things about living organisms -- they can, in a wide variety of circumstances, repair themselves. From fighting off germs to healing broken bones, the body is pretty darn resilient. Which brings up something that has always worried me about nanotechnology -- the fact that the tiny machines that have been heroically constructed by the scientists working in this field just seem so darn fragile. It's amazingly impressive what modern nano-engineers can do by way of manipulating matter at the atomic and molecular level, creating new materials and tiny machines ...