Re: Goo prophylaxis

Nicholas Bostrom (
Mon, 1 Sep 1997 12:17:13 +0000

> > = Nicholas Bostrom
> >> = CarlF
> >> > = Nicholas Bostrom
> >Carl Feynman wrote:
> > To build an optimised nano
> >self-reproducing device would be much harder than simply to make
> >something useful that can replicate.
> We're talking about gray goo here, right? That has to live in the wild,

No, black goo (deliberately designed war goo, destruction goo, doom
goo) (grey goo is accidental). What I had in mind was something that would be able to live in
the wild, but even without that ability you could still have immense
millitary advantage from being able to build unlimited amounts of
military equiptment in large tanks practically for free.

> without getting all its little cogs and conveyor belts clogged up with
> natural molecules that just happen to fit into its various nooks and
> crannies.

An easy way to fix this would be to have those inner parts isolated
from the environment.

> >For example, a universal Turing
> >machine has been constructed in Conway's Life world. The entity is
> >very big and it was hard, but nothing near a thousands of genius-year
> >task, to do it. The feasibility stems from the fact that you have
> >identical components that you can put together into bigger identical
> >components, and so on, and at each step you need only consider the
> >apparatus at a certain level of abstraction. If this is the right
> >analogy for nanotech, then the design work would seem tractable, once
> >the right tools are there. But I will take your opinion on this
> >issue into account in my future thinking. And debugging is also a
> >complication.
> I agree that Conway's Life self-replicator design could be carried out to
> completion in a short time. However, it is not a good analogy. The Life
> world is perfect, so engineering reduces to mathematics.

On the atomic level, our world is perfect too.

>Moreover, Conway
> designed his machine to function in an infinite vacuum, so the complexity
> produced by the impingement of the world is not present.

Seal it off then.

>I doubt that a
> Life self-replicator could exist in a sea of random pixels, inasmuch as any
> design for Life machinery I have seen will be completely destroyed by a
> single erroneus pixel.

What about having three (or more) of these original self-replicators,
and one unit that compares the output and kills the one whose output
diverges from the other two, and prompts the construction of a
replacement. Of course, if noise levels get too high then everything
will fall to pieces.

> >> (3) Drexler and Merkle are two very (very!) smart guys. They have labored
> >> for years, and designed what? Some bearings, a transmission, a PLA, and a
> >> Stewart platform? And you claim this shows how easy it is? I'd hate to see
> >> an engineering task you considered hard!
> >
> >Those are again optimized designs.
> No they aren't. Thay are pretty much the first designs they came up with
> that didn't explode in simulation.

I stand corrected.

> >What about the rod logic
> >computer?
> The only part of it designed to atomic precision was the PLA (programmable
> logic array) I mentioned above. Even there, only the rods were designed to
> atomic precision, not the frame that holds them, so maybe I shouldn't count it.

What is the reason why the design only went that far? Was the rest
conceptually too difficult or was it just too big for the computer
simulation to verify?

Nicholas Bostrom