The most pressing risks to human life now are Malthusian overpopulation issues, such as human-caused climate change, drought, famine, and war. Each of these issues increases the marginal utility of wealth, which decreases the attractiveness of insurance. By the time we've really messed things up, and thus need the insurance policy of extra-terrestrial colonies, we may have messed things up too much to afford a ticket out of here.So it was interesting to me to read theoretical physicist Lawrence Krauss's call for a no-return mission to Mars in the New York Times yesterday. I think it's a prescient suggestion, if one that's unlikely to be heeded. Even if there are people willing to leave Earth forever, I think our governments would be unwilling to send them. Can you imagine the repercussions if people fell prey to devastating homesickness? Diseases that couldn't be effectively cured on Mars or another planet? Sending people to space forever feels like exile, even if I think people have the right to go if they want to. I agree with ty we're probably going to need a major crisis to take that step, at least through governments, which right now are the only entities capable of backing a mission of that magnitude.
No Turning Back
Back in July, when I was writing about the greatness of Kim Stanley Robinson's Mars trilogy, commenter ty noted that: