One of the earliest proposed risks of molecular manufacturing (nanotechnology used to build products from the atom up) was “grey goo“, coined by Eric Drexler in his phenomenal 1986 book Engines of Creation. Self-replicating nanobots could escape into the environment and start devouring everything around them to reproduce, resulting in a runaway exponential destruction of the planet Earth and all its inhabitants. This horrific scenario has been repeatedly sited as a reason to curb the development of nanotechnology for molecular manufacturing, and has also been a staple of science fiction about the technology.
Eric Drexler, along with Chris Phoenix, have revisited this idea and concluded that molecular manufacturing is possible without making use of self-replicating agents. The opinion paper has been published in the latest issue of the journal Nanotechnology (the paper is available for 30 days at the Institute of Physics Publishing website, but requires a free registration to download). They conclude that simpler non-self-replicating devices would be more efficient, easier to create, and much more desirable then self-replicating nanobots. They are careful to state, however, that even stationary manufacturing systems are risky in a climate of political unrest and economic uncertainty. Such technology would have a profound and immediate effect on the world’s societies and economies.
In the United States, the nearly one billion dollars committed by the federal government for nanotechnology research is being directed primarily to developing nanoparticles for unique purposes, rather than the development of nanodevices for manufacturing. Naysayers say molecular manufacturing is simply not possible, despite the fact that nature has demonstrated the development of molecular manufacturing devices through evolution in the form of the nanobots DNA and RNA (as well as the other biological molecular machines at work in our bodies right now). Eric Drexler formed the Foresight Institute to promote molecular manufacturing. His ideas for nanotechnology form one of the major pillars of the Technological Singularity meme.