Lee Daniel Crocker wrote:
> But if that's true, wouldn't all that gray goo--indestructable and
> ravenous by definition--have long ago spread from its origins to
> devour most of our observable universe into clouds of elements and
> goo? You can't have it both ways: if life is common but always
> destroys itself with gray goo, then we must explain the apparent
> absence of the latter rather than using it to explain the absence
> of the former.
I don't see any reason why the first goo powerful enough to destroy our race and/or all multicellular life would necessarily have the capability to survive in vacuum, resist cosmic radiation, operate on solar power, and build spaceships with reentry capability. Anything that well-designed isn't an indiscriminate killer. It isn't "indestructable and ravenous by definition"; it just needs to be indestructable and ravenous enough to kill us off. There was a time when wolves came close to being that indestructable and ravenous.
That having been said, I doubt spike's Gray Filter scenario. I can see many races, even the majority, destroying themselves that way. But zero survivors? Not even one in a thousand? I don't believe it. Not even the Singularity has that kind of kill ratio - hence my guess that Singularities also suck up any other visible races.
-- email@example.com Eliezer S. Yudkowsky http://pobox.com/~sentience/AI_design.temp.html http://pobox.com/~sentience/sing_analysis.html Disclaimer: Unless otherwise specified, I'm not telling you everything I think I know.