[nzp]

> For example, his talk of Mars colonization as an escape hatch to our degradation of biodiversity / carbon emissions / etc. is just awful. What kind of idea is that?

To be fair, that's not a good characterization of why he's into Mars colonization. He's not advocating colonization so we can disregard life on Earth. He seems very much into preserving life on Earth. Mars colonization is a backup plan (or the initial stage of a backup plan) for the inevitable moment when Earth will have to be abandoned regardless of how well we behave.

Regarding “a lot of people dying” angle: the difference is in magnitude of “a lot of people”, and choice. However many people die on SpaceX spaceships, the number can never reach millions or even billions that would result from the collapse or technical decline. People also, in general, will choose to get on a spaceship and dwell on Mars, but they neither choose to be involved in dying from civilization collapsing, nor to have to fight for survival in such a situation — it would be completely forced upon them.

[johnfjacobi]

Thanks for clarifying his position. I didn't mean to suggest that he intended it to be anything other than a backup plan, but my wording might have been ambiguous because others, like Martin Rees, have suggested similar things and tend to regard them as one of the more likely outcomes of humanity's future, if the species is to survive.

> However many people die on SpaceX spaceships,

Maybe you misunderstood me. I mean that the people who don't go on SpaceX spaceships would die in a situation where that is critical to the survival of civilization.

Your choice thing doesn't convince me, but I do understand and think it is an interesting perspective. Thanks for sharing.