Wednesday, April 27, 2005


"Our experience with chemistry and physics teaches us that we do not have any idea how to make an autonomous self-replicating machine at any scale."

Lord Broers, President of the Royal Academy of Engineering, 2005
Quoted in BBC News

"Heavier-than-air flying machines are impossible."

Lord Kelvin, President of the Royal Society, 1895


Anonymous said...

There is a huge chasm the lies between the phrase "we do not have any idea how" and the word "impossible". The statements communicate essentially different sentiments. While some vague ideas have been put forth on how to build the little critters, I'd say Broers' statement is close enough to the truth to not merit attack.

Anonymous said...

There is also a huge chasm between the phrase "we do not have any idea how" and the words "already demonstrated experimentally." In point of fact, an autonomous self-replicating machine at macro scale was successfully built and operated by Jackrit Suthakorn in the Chirikjian research group in the Department of Mechanical Engineering at Johns Hopkins University in 2003, as part of his Ph.D. thesis work (see esp. Section 9.6, pp. 222-234) which is online at A movie of the device "doing it" is also available online at the JHU website, and shows the machine replicating an exact copy of itself from 4 separate feedstock components laid out on a table, fully autonomously (i.e., without any human guidance or intervention during the entire replication process), in a mean time of 135 seconds averaged over dozens of independent runs. Critics may quibble over definitions, sputtering and harrumphing "yes, but that's not what I meant by ..." (the same class of objection leveled against AI after a computer became world checkers champion, decades ago). But the quoted statement by Lord Broers, if accurately reported by BBC, is factually incorrect.

An extensive technical discussion of the Suthakorn-Chirikjian replicator and many related examples, accompanied by hundreds of illustrations and thousands of references, is provided in the recent survey book by Freitas and Merkle, Kinematic Self-Replicating Machines (Landes Bioscience, 2004), still available in hardcover at Apparently either Lord Broers or the advisors he unwisely chose to rely upon are unfamiliar with the existing literature on self-replicating systems. They deserve to be educated, not attacked.

Howard Lovy said...

Absolutely, Jim. I'm aware of the difference between the two statements. There is a huge chasm of time and context between them, too.

Lord Kelvin likely legitimately believed that flight was impossible, unless there is a political context in 1895 that I'm not aware of -- perhaps some irresponsible pamphleteer was warning that not only was flight possible, these hypothetical "flying machines" could someday be used to drop bombs on London. Well, such an impossible scenario might have prompted England's most prominent scientist to emphasize that not only was such a thing unlikely, but also defied the known laws of physics.

In any case, Lord Kelvin made up for that error in other ways. You know, sometimes you're hot, sometimes you're not.

What distinguishes today's naysayers is how they go out of their way to say what is not possible. It has always struck me as odd that men and women of science should so emphatically pooh-pooh the same idea using roughly the same language. It reminds me of the political "talking points" collages that Jon Stewart of "The Daily Show" puts together after the Sunday talk shows.

Whether Smalley, Whitesides, Broers and others truly believe that molecular manufacturing is impossible is really beside the point. They are making these statements repeatedly because they believe the public must be soothed into believing that nanomaterials are being harnessed only for mankind's benefit. So, not only is it unlikely to get out of control, it's physically impossible for things to go wrong, everything is OK, please go back to your homes, nanobots do not and cannot exist. Nothing to worry about. …

Have you ever heard of a scientific concept so vehemently attacked in modern times?

The fallacy here is that the public needs to be reassured that the very concepts that make nanotechnology so fascinating to the general public can never really happen. That will not make anti-nanotech agitators go home. They're still here, and gaining in strength despite the best efforts of "leading scientists" to "reassure" the public.

What they do not see is that molecular manufacturing is what gets the public turned on and engaged in the first place. What is wrong with embracing it as a goal -- even if a distant one? That's what will get the public excited, and will inspire the next generation of nanoscientists to flood these new nanotech centers opening up around the world.

The chorus of grumpy old men chanting "impossible" does nothing to soothe the public. If anything, it makes them lose interest entirely.

Anonymous said...

Howard, you should check your sources. What Broers said, according to the transcript, was " But to date there has been no experimental verification that such machines could be built or that there are mechanisms by which they could replicate. There are not even proven ways to model such structures. " Your sentence was quoted by Broers, but it's actually from the Royal Society report that's now nearly two years old.

Are you suggesting that scientists should publicly embrace molecular manufacturing as a goal to keep the public excited, even though they privately don't believe it's possible? That seems to me to be a strategy that is both cynical and dangerous.

Anonymous said...

Howard: Comparing and contrasting quotes is useful for highlighting perspectives at a glance.
Jim and Richard: Sorry, but even when littered with "Chicken Little" type hysteria, "killing the messenger" is such a yawn...
To think that because we don't have an idea today, means we won't tomorrow, denies the reality of learning and growth. Why defend impossiblity when there is room to investigate what is possible? What are you afraid of? Oh that's right, I forgot: Howard's "cynical and dangerous" "attack" might cause the sky to fall. Run for the hills, boys!

Anonymous said...

I wasn't in any way accusing Howard of making a cynical and dangerous attack, as rereading my comment should make absolutely clear. As to investigating what is possible, I've written a book that's done just that. Have you read it? If you had, you would know that what I'm arguing is not that radical nanotechnology isn't possible, it's that it won't take the form that molecular manufacturing enthusiasts foresee. The reality of learning and growth is that you have to revise your ideas as you learn more. If you can't do this, what you are left with is nothing more than dogma.

Anonymous said...

Clarke's Law states "Any sufficiently advanced technology is indistinguishable from magic."

Do you belive in magic? I do. I see it every day.

PS Don't run for the hills. The sky is closer there.

Anonymous said...

The thing that strikes me about the two quotes the intellectual effort that must have took to ignore the biological world. Birds and insects are heavier than air yet many birds and insects are capable of flying. All life is based on the ability to self-replicate but Lord Broers says “no experimental verification that such machines could be built or that there are mechanisms by which they could replicate.”

Anonymous said...

What I said was that if scientists were to publicly embrace molecular manufacturing as a goal to keep the public excited, then that would be cynical and dangerous. Clear enough now?

Howard Lovy said...

Let's stay on topic and refrain from personal attacks. Richard, I apologize for the comment that used to be above yours. It's deleted now.

Anonymous said...

Greetings, Dr. Jones (and all you disembodied personalities),
Make that "...if skeptical scientists..." and I think we're golden. I gave up on public excitement when I found out you couldn't call it "NUCLEAR magnetic resonance imaging" any more. (

In the immortal words of the late Adam Clayton Powell, Jr. ...

keep the faith, baby!
Damian Allis

MrEntropy said...

I'm not sure I understand where all the confusion comes from. To find out why this technology is attacked you need to look at what everyone has to lose.

If we go totally fantastic for a moment, and really let our minds go it's easy to see why a lot of people would not want to see molecular manufacturing or item self-replication exist.

For example, I think it was in "Engines of Creation" where a bit about solar collectors built into roadways was mentioned. What would the local power companies have to lose if energy was stored all day long on highways, or roofs of houses? Energy costs would plummet, especially if a house could capture enough solar energy to keep it running all night.

Let's get even crazier. Let's say that you can have a device in your house, say slightly bigger than a kiddie pool, that acts as your molecular manufacturing plant. Toss in some garbage or grass clippings, maybe some old scrap metal. Pick an item from a menu and it's "grown" for you. Sure, that'd make the general populace happy, but it wouldn't do anything for, say, GE, if you needed a new toaster.

The utopian vision of molecular manufacturing is scary. It would, literally, change life as we know it. It would shift the power structure, the money structure, and everything we've lived with to a whole new group.

Artisans and molecular engineers would be the ruling class. Think about it: artists. What seperates the ring your wife wears from the ring your neighbor has? The design. You would buy designs from an artist, who would have the molecular engineer do the programming. But what would you pay them with? If your energy is nearly, if not actually, free and you can have household items for the cost of your weekly garbage what kind of jobs would be available for you to get an income? And would you really need one? Presumably. After all, we'll always have taxes.

Oh. I forgot about doctors and insurance companies. You're not feeling well this morning? Pop this pill. An army of nano-docs runs through your blood stream targeting known illness' and taking care of business. How annoyed would your HMO be about that?

Did your TV go on the fritz? You'd never know it. The nano-repairbots have noticed the potential break in a circuit and have already repaired it. Bye-bye, Joes Television Repair Shop.

Need a faster computer? Someone uploaded programming to increase the efficiancy. You've downloaded it and your computer has already re-configured itself and given you the speed gain you need. You don't need anymore storage, because the molecules in your desk take care of that.

This "grey ooze" argument is just a red herring. It's not the real fear, it's the fear that can sway the general populace. What consumer would be afraid of a self-repairing car? Or growing another hammer because they lost the last one in the weeds? Nobody. But we'd be really afraid of waking up in a bed of grey ooze.

But what scares the current power structure?

Yes, this is a simplified argument. And it does require a leap of faith that ME is possible, etc. And it is 6am and my brain is still not firing on all four cylinders yet. But all you need is one person in a think tank to bring this up and you can see where they would go with it. It'd be like Stephen King reading bedtime stories to a group of pre-schoolers. They'd all sleep with a night light on, fearing evil nanobots that steal their income while they sleep.

Anonymous said...

Unfortunately for you folks, the ride to work gave me time to think so I thought I'd add a bit more about the "grey ooze" threat.

I don't worry too much about the entertainment media casting a dark shadow on nanotechnology. For years we've had books and movies warning us about computers and/or robots taking over the Earth ("Demonseed", "Tron", "The Terminator", "The Matrix"). But darned if Sony isn't still making a robotic doggie. And V-Tech makes laptops for kids. Those movies and books haven't fooled anyone longer than it took to polish off a bucket of popcorn. So Michael Crichton's "Prey" isn't too big a threat.

Robots and computers don't hurt anybody. Well, nobody important. Julian, who lost his job to a robot on the assembly line, may be hurt but not Bill, the guy behind the desk who signed the approval for the robots.

As far as Bill is concerned, robots on the assembly line mean a cheaper product. So now consumers can buy the product at a slightly reduced price and the company can make a bigger profit from the markup. The fact that people like Julian can no longer buy the product, because they are unemployed, doesn't make a difference. There are many other people still employed that can.

This is why you don't see politicians speaking out against robots and computers: they're good for business and may, ultimately, be good for the consumer. Nobody is afraid of the assembly line droids walking out of the building and taking over the Earth in the name of their AMD, Intel, and Motorola Overlords.

Get people dreaming about nanotechnology, though, and it's an all new ballgame. Would it matter if Julian lost his job to a nano-fabricator? Not if he could go home and still provide for his family. But if he could put new tires on his car by tossing his old tires into a deconstruction vat and then have them rebuilt in his own fabricator it would be bad for business. Good for the consumer, bad for business.

I'm sure there's a few white coats who think I'm being vastly unfair by concentrating on this utopian vision, but that's the way the common person thinks. They don't care about the mechanism that changes their antibodies into Robocops, just that it works. And, if it works a little bit, people are going to dream bigger. It's the way we are.

I imagine even a hard core physicist, who is watching Star Trek while making dinner for six, would look at a replicator and think, "Totally impossible! But, boy, wouldn't that be handy." Nobody is completely immune to science fiction and fantasy. That's why they exist.

So, if you're part of the ruling class, what do you do? You need to keep the expectations of the public low, lest they get too grandoise in their dreams. You need to make sure you keep your power base.

You create fear and uncertainty. If you had molecular manufacturing you could have self-replicating nanobots. And they would run amok and self-replicate using the entirety of the Earth (including you!) to make more of themselves. But it can't happen. It's impossible. Completely impossible. But that doesn't mean you shouldn't be afraid of it. You should be.

Howard Lovy said...

I see now why you're called Mr. Entropy ...

Start from two, simple, orderly quotations and chart the trend to chaos. Thank you, everybody. Let's close this this discussion and move on. You can read Eric Drexler's response here. Thank you, folks.