A belief in the power and imminence of the Drexlerian vision of radical nanotechnology is part of the belief-package of adherents of the view that an acceleration of technology, linked particularly with the development of a recursively self-improving, super-human, artificial intelligence, will shortly lead to a moment of ineffably rapid technological and societal change – the Singularity. So it’s not surprising that my article in the IEEE Spectrum special issue on the Singularity – “Rupturing the Nanotech Rapture” – has generated some reaction amongst the singularitarians. The longest response has come from Michael Anissimov, whose blog Accelerating Future offers an articulate statement of the singularitarian case. Here are my thoughts on some of the issues he raises.
One feature of his response is his dissociation from some of the stronger claims of his fellow singularitarians. For example, he responds to the suggestion that MNT will allow any material or artefact – “a Stradivarius or a steak” – to be made in abundance, by suggesting that no-one thinks this anymore, and this is a “red herring” that has arisen from “journalists inaccurately summarizing the ideas of scientists”. On the contrary, this claim has been at the heart of the rhetoric surrounding MNT from the earliest writings of Drexler, who wrote in “Engines of Creation” “Because assemblers will let us place atoms in almost any reasonable arrangement , they will let us build almost anything that the laws of nature allow to exist.” Elsewhere, Anissimov distances himself from Kurzweil, who he includes in a group of futurists who “justifiably attract ridicule”.
This raises the question of who speaks for the singularitarians. As an author writing here for a publication with a fairly large circulation, it seems to me obvious that the authors whose arguments I need to address first are those whose books themselves command the largest circulation, because that’s where the readers are mostly going to have got their ideas about the singularity from. So, the first thing I did when I got this assignment was to read Kurzweil’s bestseller “The Singularity is Near”; after all, it’s Kurzweil who is able to command articles in major newspapers and is about to release a film. More specific to MNT, Drexler’s “Engines of Creation” obviously has to be a major point of reference, together with more recent books like Josh Hall’s “Nanofuture”. For the technical details of MNT, Drexler’s “Nanosystems” is the key text. It may well be that Michael and his associates have more sophisticated ideas about MNT and the singularity, but while these ideas remain confined to discussions on singularitarian blogs and email lists, they aren’t realistically going to attract the attention that people like Kurzweil do, and its appropriate that the publicly prominent faces of singularitarianism should attract the efforts of those arguing against the notion.
A second theme of Michael’s response is the contention that the research that will lead to MNT is happening anyway. It’s certainly true that there are many exciting developments going on in nanotechnology laboratories around the world. What’s at issue, though, is what direction these developments are taking us. GIven the tendencies of singularitarians towards technological determinism, it’s a natural tendency to assume that all these exciting developments are all milestones on the way to a nano-assembler, and that progress towards the singularity can be measured by the weight of press releases flowing from the press offices of universities and research labs around the world. The crucial point, though, is that there’s no force driving technology towards MNT. Yes, technology is moving forward, but the road it’s taking is not the one anticipated by MNT proponents. It’s not clear to me that Michael has understood my central argument – it’s true that biology offers an existence proof for advanced nanotechnological devices of one kind or another – as Michael says, “Obviously, a huge number of biological entities, from molecule-sized to cell-sized, regularly traverse the body and perform a wide variety of essential functions, so we know such a thing is possible in principle.” But, this doesn’t allow us conclude that nanorobots built on the mechanical engineering principles of MNT will be possible, because the biological machines work on entirely different principles. The difficulties I outline for MNT that arise as a result of the different physics of the nanoscale are not difficulties for biological nanotechnology, because its very different operating principles exploit this different physics rather than trying to engineer round it.
What’s measured by all these press releases, then, is progress towards a whole variety of technological goals, many very different from the goals envisaged for MNT, and each of whose feasibility at the present time we simply don’t know. I’ve given my arguments as to why MNT actually looks less likely now than it did ten years ago, and Michael isn’t able to counter these arguments other than by saying that “Of course, all of these challenges were taken into account in the first serious study of the feasibility of nanoscale robotic systems, titled Nanosystems…. We’ll need to build nanomachines using nanomechanical principles, not naive reapplications of macroscale engineering principles.” But Nanosystems is all about applying macroscale engineering principles – right at the outset it states that “molecular manufacturing applies the principles of mechanical engineering to chemistry.” Instead of work directed towards MNT, we’re now seeing other goals being pursued – goals like quantum computing, DNA based nanomachines, a path from plastic electronics to ultracheap computing and molecular electronics, breakthroughs in nanomedicine, optical metamaterials. Far from being incremental updates, many of these research directions hadn’t even been conceived when Drexler wrote “Engines of Creation”, and, unlike the mechanical engineering paradigm, these all really do exploit the different and unfamiliar physics of the nanoscale. All these are being actively researched now, but not all of them will pan out and other entirely unforeseen technologies will be discovered and get people excited anew.
Ultimately, Michael’s arguments boil down to a concatenation of ever-hopeful “ifs” and “ands”. In answer to my suggestion that, if MNT like processes could only be got to work at low temperatures and ultra-high vacua, Michael says “If the machines used to maintain high vacuum and extreme refrigeration could be manufactured for the cost of raw materials, and energy can be obtained in great abundance from nano-manufactured, durable, self-cleaning solar panels, I am skeptical that this would be as substantial of a barrier as it is to similar high-requirement processes today.” I think there’s a misunderstanding of economics here. Things can only be manufactured for the cost of their raw materials if the capital cost of the manufacturing machinery is very small. But this capital cost itself mostly reflects the amortization of the research and development costs of developing the necessary plant and equipment. What we’ve learnt from the semiconductor industry is that as technology progresses these capital costs become larger and larger and more and more dominating for the economics of the industry. It’s difficult to see what can reverse this trend without invoking a deus ex machina. Ultimately, it’s just such an invocation that arguments for the singularity seem in the end to reduce to.