A lot of people back up the data on their computers. It doesn't mean they're planning to throw their computers away.

The heated reaction to Hawking on this really surprised me. I had thought that his view was pretty much ubiquitous common sense before this episode.

I think the naivete of this viewpoint is tremendous, although it's so tempting that I'm not surprised that otherwise-intelligent people seem to cling to it.

Here's my thesis: I think we will find, in the fullness of time, that human beings are more integrally linked, in some fairly profound neuroendocrine way, to the specific conditions of Terrene existence, than we currently suspect.

I don't mean to get all Gaian and gushy sounding, but my bet is that we're a part of this place at a very deep level, and that we disregard this connection only at the gravest risk to our wellbeing both personal and communal.

What I believe, but cannot prove (to use a handy, if trendy formulation), is that human life will never take healthy root off of this sphere. We were not meant to be the vehicle for the propagation of Mind throughout the observable universe, for better or worse - and therefore we're going to have to come to terms with the requirements of equilibrium in the closed and unpredictable system we do have.

I agree this is pretty common place and anybody having opened a science-fiction book already has this thought in mind.

However I think we need to stress it again and again as people are pointing at the costs of space exploration and ask "do I get value for my tax money ?" in the same way shareholders are scrapping the R&D budgets of firms.

Thinking of those challenges ahead will also help mankind to feel more and more united and repair the damage caused by hundreds of years of religion or race struggles.

Anyway nothing new in there.

I disagree with Adam on two points.

1) There doesn't need to be any handwaving about subtle yet "profound neuroendocrine" linkage between humans and Earth.

The linkage is already obvious to cosmonauts of long duration spaceflights. The human body progressively deteriorates in low and microgravity environments.

This poses a profound barrier for human migration to other worlds. At the moment there isn't much we can do to slow or reverse these effects. But this brings me to the second point of disagreement.

2) If we take terraforming seriously why can't we bioengineer ourselves to thrive in low and microgravity environments?

The biological barriers, either Adam's handwaving or my real one, will one day be bypassed through bioengineering. As human culture spreads out, humans may diversify into many different species each well-suited for the environments they live in.

Maybe one of the reasons why Hawking proposed this idea is that he himself has direct experience with using technology to survive and thrive. In a way, Hawking *is* a cyborg--fyborg actually.

And he's paid and trained to think big. I'm certain it wasn't his intent to say the Earth is somehow disposable. If anything he's trying to think of ways to ensure the longterm survival of the Earth. If human culture survives, we can work to save the Earth from all kinds of threats, most especially ourselves.

Pace, thanks for that snide dismissal of my comments as "handwaving." Top marks in the congeniality department!

I am aware of what the long-orbital-duration cosmonauts experienced in microgravity, as well as the crews of Mir, Skylab, and the ISS. But I'm also thinking of the earlier French cave-dwelling studies, and the statistically significant (but, of course, potentially not causally linked) incidence of later suicide in the cohort of volunteers. I'm making assumptions and extrapolations based on what I know, too, of the experience of Antarctic-station personnel who winter over, of submarine crews, and of other groups of human beings who have been confined to enclosed spaces for long stretched of time, cut off from the ordinary circadian cues. You'll stipulate, surely, that the record is not encouraging.

But that's not really where I take issue with your stance. Where I depart ways with you quite profoundly is in your utterly unwarranted optimism about "bioengineering ourselves," which crops up time and again in posthumanist/Extropian circles and which has always struck me as an adolescent wish-fulfillment fantasy little short of risible - and a splendid example of extrapolating beyond the data.

I mean, if bioengineering is so simple, why don't we bionengineer out all of those less-salutary, wasteful primate qualities and attributes that have made us such poor stewards of our home planet? We could all be hardwired to be resource-conservative, strategic, cooperative thinkers at the molecular level. How very wonderful that would be.

Or not. How about this instead? How about designing within the observed constraints presented by humanity as it is, instead of waiting and wishing for some geekz0r deus ex machina to save our bacon? Any solution to our very substantial problems that doesn't begin and end with a frank acceptance of human nature (as it has been observed to operate across times, places and cultures) is a total nonstarter.

AG, bioengineering to change a physiological reaction to a change in external environment is qualitatively different from bioengineering to change behavior. Behaviorally, human nature is much more flexible than you appear to credit. At the same time, we've been using the functional equivalent of geekz0r deus ex machina for millennia to improve our physiological nature.

Frankly, bioengineering to change our bodily reactions to zero-gee (or whatever) is probably *less* of a major shift than was urbanization.

The reaction to Hawking's comments didn't really suprise me. I've heard similar comments on the BBC website a few months ago in their "Have Your Say" section on the subject of a manned mission to Mars.

There seems to be a connection in some people's minds between manned space travel and a betrayl of this planet. It's irrational in my view but I don't see it changing anytime soon.

More troubling we have environmental groups in the UK calling for a ban on scientific research in genetic engineering (doubly ironic because their earlier objections was that more research was necessary) and more recently nanotechnology. Hopefully this won't go far but there's growing discontent amongst deep ecologists with science and technology in general. It's a worrying trend that bears watching.

Adam,

I apologize for dismissing profound neuroendocrine linkage thing as handwaving but, I've yet to see a lot of widely accepted evidence for it so, until then, in my book, it's handwaving. I have to see clear evidence for the biochemistry you're speculating about before I'll decide to stop referring to it as handwaving.

Would you perhaps point me to some studies or news stories about suicides among long duration Antartic residents, submariners, SAD sufferers or the cave dwelling experiment?

Anyway, I suppose I'm equally guilty on one or more levels of handwaving myself. To resort to the vague statements about bioengineering is also a kind of handwaving. I would like to believe that there is more support for my position but, really, all we can do is wait and see.

Is any fundamental aspect of human nature immutable or not? If they are immutable, then we're stuck here and space will remain forever unhealthy for us.

Regardless, if we're forced to stay or if we can go, I think we can fix and restore this planet. We just have to make the political, social and economic changes. We also have to invent the new technology that will help us do this.