Nanomachines In Nature

One of the reasons we know that the construction of nanomachines is possible is that we are surrounded by them all the time. In fact, we consist of them. Take for example proteins. Nature accomplished the engineering feat of nanomachinery through evolution, and now we are trying to catch up.

"All machines use clumps of atoms as parts. Protein machines simply use very small clumps."
-EOC, Drexler

Because nanomachines exist in nature, moving, analyzing, reacting, photosynthesizing, etc. we know that they are scientifically feasable. We can't build them now only because we don't have the technology to really properly work on that scale. It's only a matter of time before we have that technology (we are making steady progress in the area today) and when we do, nanotechnology will permeate into every aspect of our lives.

Sources
http://foresight.org/EOC/EOC_Chapter_1.html
http://WWW.Physik.TU-Muenchen.DE:81/~misch/
http://www.di.com/
http://surf.eng.iastate.edu/~karie/SEM.html

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