Re: Our rocky solar system may be rare

Robin Hanson (rhanson@gmu.edu)
Fri, 17 Sep 1999 14:26:14 -0400

I wrote:
>Robert Bradbury wrote:
> >Look at my comments on Robin's paper at:
> > http://www.aeiveos.com/~bradbury/GreatFilter/
> > Somewhat out of date because of the more recent work I've done.
>
>I ... will try to respond within a week.

OK, here goes.

I wrote:
>we expect internally-competitive populations of our surviving descendants to
>continue to advance technologically, and to fill new niches as they become
>technologically and economically feasible. Colonization has been the
>consistent human experience over the long run, and our best understanding of
>social systemsdoesn't suggest otherwise. While humans evolve within complex
>co-evolving organizational, cultural, memetic, and genetic systems, all of
>these systems show long-term tendencies to make use of reproductively-useful
>resources.

Robert replied:
>Fish do not "mutate" into birds and birds do not "mutate" into fish. For
>evolution to occur, ecological niches must be substantially similar for
>gradual adaptations. The history of the planet is testimony to situations
>in which environmental changes required adaptations that were too great for
>many species and mass extinctions resulted. The only exceptions to this are
>when "consciousness" allows one to design and build "organisms" which are
>capable of survival in radically different environments. Intelligence
>allows one to comprehend the survival requirements of different environments
>and create organisms/machines which are capable of populating it. Those
>organisms/machines will not have our genetic drive to expand unless we
>intentionally imbue them with it. They are not our "descendents", they are
>either our "creations" or perhaps "us". Many individuals significantly
>question whether of human violence or endless expansionism make sense for an
>"intelligent" species. It is questionable whether we would program this
>trait into our creations or would continue to promote these traits within
>ourselves in light of our current perspectives. There are only three
>possibilities, "more", "different" and "better".
Nature tends to favor
>"more" because it enables "different" and "better". Lacking intelligence,
>history, wisdom, simulation capacity, etc. it is impossible for nature to
>create "different" and "better" by design. Creative intelligent engineering
>does not suffer from the handicaps of nature and need not follow the
>unconscious dictates of "more". ...

But we *are* nature. At first maybe only rocks were around, then cells, then animals, now us, at later space-faring progeny. We are more intelligent than our ancestors and current competitors, but we do and will still evolve. Natural selection will continue to apply to us and our progeny, or whatever you want to call them. It won't be selection primarily of genes, but that hardly matters. Intelligence may change pressures toward violence, by allowing the evolution of institutions which allow cooperation via peace. The creation and preservation of such institutions is in the individual interests
of many competing entities. But I can see no similar change in the pressures toward expansionism; it seems in no particular individuals interest to prevent it. And intelligence vastly increases our ability to expand.

>But self-engineered immortal beings do not "reproduce", they only evolve.

But of course they "reproduce", as do species, corporations, nations, and cultures. They have traits, causally produce identifiable progeny, and traits are heritable to progeny. QED. There are future beings who are causally similar to certain past beings, and that's all it takes.

>Again, what if our "decendents" are us? Would we choose to colonize? If
>you had a choice of putting energy/mass resources into something which
>expanded your personal capacities or abilities vs. putting energy/mass
>resources into something which was beyond your "control", which would you
>tend to favor?

People put resources into creating children all the time. And believe me, children are beyond your control. And all it takes is for some entities to do this, you don't need all or even most. Then evolution takes over.

>One possibility is to only colonize systems in which the other entity
>(entities) growth rate(s) is greater than your local growth rate, so that
>it will eventually surpass you.

This is a prediction of my model, by the way.

>More mass eventually results in a black hole that disappears from the
>universe. More energy eventually results in something which melts itself.
>There are significant limits on the structures which are universe allows.
>There is no point to creating or promoting "remote" individuals if by the
>time their information reaches you it is "old news".

What "point" there is depends on one's preferences. There is no law that says the only interest one can have in colonies is to get "news" later. Even if there were such a law, that still doesn't preclude colonies for the sufficiently patient. (And I expect evolution to make creatures sufficiently patient.)

>The most interesting question is why is the remaining 10% of the galaxy
>undeveloped? This is a variant of the Fermi Question (paradox). The best
>answer I have is that seeing stars may be a strong motivator for developing
>civilizations to advance to the superintelligence level.

I don't follow this at all. Surely if we looked out into space and saw vast galactic engineering projects, *that* would spur us all the more to advance to a level where we could find out what they are and maybe make some of our own.

>They could easily be among us and we would not know it. We do not posess
>the biotechnology capabilities to differentiate an alien imposter from a
>"genuine" human. They could exist even a few miles below the surface of
>the Earth and we would not know
it.

Sure, and God could create a universe 6000 years ago with all the light on the way to Earth, so it just looks like its 13 billion years old. And aliens could surround our solar system with a big TV screen showing the universe we see. But the big question is: WHY? Why would they do this?

>Exactly! The key words are "advanced competitive life" and "we see". The
>time to evolve from our current level to a fully advanced nanotechnological
>civilization appears to be less than 50 years. If they are here, their
>motivations, goals, thoughts, appearence, etc. are significantly beyond our
>comprehension.

I disagree that their motivations and appearance are beyond comprehension. We understand many things about physics, evolution, and society. We must use what we know to evaluate the theory that invisible aliens are all around.

 >As pointed out by Drexler in Nanosystems, pgs 154-156, radiation is a
 >signifiant hazard to nanomachines.  ...  It is even a significant problem
 >for not quite nanoscale human machines.  ...  It may not be possible to
 >construct a probe capable of traveling significant interstellar distances at
 >high speeds and survive.

I think it is clear that you can make a probe large enough that shielding will be sufficient. Larger probes are more expensive, but we're considering civilizations that have thoroughly colonized a whole star system. For such civilizations, I don't think the expense prohibitive.

>The problem is whether or not a superintelligence constitutes a "competitive
>population". A Dyson Shell superintelligence constructed from nanocomputers
>(1 cm3) has the capacity to hold a trillion trillion human intelligences.
>The communication bandwidth between the processor elements is so high that
>it is questionable whether individuals would really exist.

Such a shell would be so complex, and modularity is such a powerful way to deal with complexity, that I can't imagine that it wouldn't have "parts" in some sense. And it is very hard to prevent competition among parts, no matter what the intention of anything is.

>It need not be a "common zoo". It could just as well be that there are
>desirable zones of habitation for superintelligences and we aren't in one of
>them. The outer galactic halo is desirable for its low radiation levels.
>The center of the galaxy is desirable because of high energy levels and very
>short inter-stellar communication times. The outer regions of the galactic
>bulge are desirable for low radiation and inter-stellar communication times
>significantly shorter than those for stars distributed throughout the
>galactic halo. The arms of the galaxy seem to have little merit. Assuming
>that heavier elements are of more value to superintelligences than lighter
>elements, some portion of the galaxy has to be left for star formation,
>evolution and super novas unless star mining and large scale matter
>transmutation are activities that superintelligences want to undertake.
>There may also be intergalactic beauty competitions occuring every billion
>years or so and galaxies with all the stars enshrouded don't even make it to
>the semifinals.

You seem to imagine a curious mix of terribly advanced beings abandoning vast regions for very minor reasons. Its like saying that no people live in Indonesia because it has more sun, is more humid, and some place has to be left to grow trees. Surely beings that could survive the inner galaxy could shield themselves enough to survive here. And surely the most efficient way to create heavy elements isn't to leave stars exactly the way they are.

>They didn't colonize absolutely everything. ---- There is no point when the >returns on investment relative to the risks are so low.

What is the basis for this calculation? What risks do you have in mind, and what interest rate are you assuming?

Robin Hanson rhanson@gmu.edu http://hanson.gmu.edu Asst. Prof. Economics, George Mason University MSN 1D3, Carow Hall, Fairfax VA 22030
703-993-2326 FAX: 703-993-2323