The BBC is reporting that nanotechnologist Eric Drexler is backing away from his famous claim that nanomachines could turn the planet into “grey goo”. Some two decades ago Drexler warned of the possibility that self-replicating machines could overrun the planet, destroying life as we know it. He now says he was outlining the worst-case scenario.
It’s worth noting though that he stops well-short of saying it is impossible – indeed, it seems the major reason for recanting is simply that he believes too many restrictions have been placed on nanotechnology as a result of his statement. His turnaround also appears to be based only on the case of ‘controlled’ nanotechnology…as with nuclear and biotech, the real problem is when it gets into the hands of ‘the enemy’.