You have been 'grey gooed'

Hysteria has set back real discussion of nanotechnology, says K. Eric Drexler

The Institute of Physics recently issued a press release, "Nanotechnology Pioneer Slays Grey Goo Myths", on the publication of an article that Chris Phoenix and I wrote, "Safe Exponential Manufacturing". Talk of runaway self-replicating machines, or "grey goo", spurred fears that have hampered rational public debate about nanotechnology and has diverted attention from serious issues including research paths and strategic competition issues.

Chris Phoenix and I have tried to set the record straight.

The message of the paper is that non-self-replicating systems provide a simpler and more efficient way to perform molecular manufacturing. Hence, there is no incentive for anyone to do the difficult engineering work needed to make anything remotely like a runaway replicator. Advanced nanotechnologies raise serious concerns, but the "grey goo" scenario is an obsolete distraction.

Media coverage has presented sometimes incoherent summaries. For example, the Sydney Morning Herald in Australia reported: "The scientist who first raised the alarm about grey goo destroying life on Earth now says 'there is nothing to fear from nanotechnology', but two sentences later, says 'a far more serious danger is the possibility of nanotechnology being used to make powerful non-replicating weapons'." I have been described as both a proponent and an opponent of nanotechnology, but here we see both poles in the same paragraph.

I introduced the term nanotechnology in my book Engines of Creation (1986) to describe physicist Richard Feynman's vision of nanomachines creating atomically precise products. At the time, I feared that the public might become so enamoured of the potential benefits - such as curing cancer or eliminating dependence on hydrocarbon fuels - that they would ignore the downsides. I sketched a worst-case scenario so that those learning about nanotechnology would consider potential risks alongside the benefits.

I expected that contemplation to cause some discomfort but not that depictions of swarms of self-replicating nanobugs would dominate popular perceptions of advanced nanotechnology. Nor that the term "nanotechnology" would come to describe a wide range of almost unrelated research fields, and that efforts to disassociate those fields from concerns about "grey goo" would spur false scientific denials of the original concepts.

The resulting pattern of denial and polarisation has hindered research and discussion. This is ironic because studies of molecular manufacturing began discarding small self-replicating systems more than a decade ago. Although runaway replication is not forbidden by physical law, an overemphasis on this scenario has diverted attention from more pressing issues.

Several people have asked me, if I could turn the clock back 20 years, what would I do differently? I still think it would have been irresponsible to describe the benefits of nanotechnology without addressing the potential risks. I would, however, have chosen a less appealingly alliterative term than "grey goo". If a similar scenario had been named "deliberately engineered dangerous self-replication", it would have had a lower profile.

Also, I would have begun describing molecular manufacturing as based on desktop-scale factories with nanoscale parts sooner, rather than a biologically inspired process. This would have tended to displace the image of swarms of nanobugs with that of a bulky machine with a fan, small rubber feet and no more mobility than a desktop printer.

That, in turn, would have helped to place the focus on the real risks. The chief danger is not what nanomachines might do by accident. It is instead the consequences, both intended and unintended, of what people choose to do with powerful new technologies in a world dominated by economic and strategic competition. This is what we need to discuss today.

K. Eric Drexler is founder of the Foresight Institute Los Altos, California.