[JumpCrisscross]

> our population is, at this time, growing exponentially

Not in advanced (i.e. materially intensive) economies. And global population models are currently all aiming towards stabilization.

> this is an argument that sustainability is a prerequisite for space travel and not the other way around

How so? Without space travel, there is no near-term incentive to develop those technologies. (The terrestrial incentives are all long term.)

> Are these hypothetical civilizations on the brink of unlocking space travel? Or are they 100 years away?

China and America are technologically within a decade of establishing Moon and Mars bases. Not permanent, independent settlements. But settlements that need to be as self-sustaining as possible nevertheless on account of launch costs and travel time.

> that's a natural experiment which roughly addresses this question

I see a different reading. We got a lot of sustainability-progressing technology out of the space race.

Alignment with the goal of human colonization wasn’t yet there. But there are reasons to be optimistic with modern materials, bioengineering and computational methods. Methods that could very easily also yield literal fruits that make our economies more sustainable at home.

[maxbond]

> Without space travel, there is no near-term incentive to develop those technologies.

Of course there is. Our climate is getting less hospitable, right now, in our lifetime. Storms are stronger, wildfires are more frequent and severe, we're beginning to strain our fresh water aquifers, etc. We are seeing really alarming rates of decline of flying insect biomass and other signs of an ecosystem in distress, and that ecosystem provides us with trillions of dollars of value. There is no human industry without our ecosystem to support us.

Solar, wind, etc. are also getting more and more competitive with fossil fuels, providing a purely monetary incentive.

And if we disregard all long term incentives, who cares about space? Even if we use very optimistic figures we're not going to be exploiting extraterrestrial resources for a few decades. And if we encounter significant setbacks (which I have to imagine we will) that take quite a long time.

> China and America are technologically within a decade of establishing Moon and Mars bases.

I'll believe it when I see it. But if this is true, then wouldn't you say, by your logic, that this is a near term incentive for developing sustainable technologies?

> But there are reasons to be optimistic...

I agree. I don't think we really disagree in principle on any of this. I think we have different values and different levels of skepticism (or perhaps are skeptical of different things) but broadly/directionally agree.

[JumpCrisscross]

> if we disregard all long term incentives, who cares about space?

The short-term incentives string together into a long-term plan.

> Our climate is getting less hospitable, right now, in our lifetime. Storms are stronger, wildfires are more frequent and severe, we're beginning to strain our fresh water aquifers, etc. We are seeing really alarming rates of decline of flying insect biomass and other signs of an ecosystem in distress, and that ecosystem provides us with trillions of dollars of value

Which has been enough urgency to do what exactly?

> Solar, wind, etc. are also getting more and more competitive with fossil fuels

Great example of folks pursuing short-term profit incentives making progress towards a long-term goal.

> if this is true, then wouldn't you say, by your logic, that this is a near term incentive for developing sustainable technologies?

If we try. Yes. If we gut those programmes, no. (For the technology benefits we just have to try.)

> we have different values and different levels of skepticism (or perhaps are skeptical of different things) but broadly/directionally agree

I think so too.

I think some people are motivated by stewardship and others by exploration. Focusing one one at the expense of the other is a false economy. And pursuing both doesn’t necessarily mean a long-term trade-off.

[maxbond]

> The short-term incentives string together into a long-term plan.

Sustainability isn't different in this regard. Eg, algae farming is a promising way to produce protein and fix carbon. But the economics aren't there yet, so commercial algae farms are pursuing higher margin markets like supplements and inputs to cosmetics rather than food (with the notable exception of feed in aquaculture like salmon).

When solar was still very expensive it was deployed in weird environments like satellites and oil fields where the grid wasn't available. But that proved to be stepping stones to a much larger solar industry.

> Which has been enough urgency to do what exactly?

Lots of stuff, for instance the €5.5B MOSE seawall built by Venice and various projects along the Colorado River to secure the water supply of the southwest USA (to pick just one, Las Vegas' Third Straw at around $1.3B). When disasters happen we obviously spend hundreds of millions to a billion+ on cleanup, rescue, etc. It's also been urgent enough to drive a huge amount of research, advocacy, etc.

Granted, those are fairly low numbers in the scheme of things. But the inaction is driven by interests who stand to lose money, not by economic rationality. I don't think even those monied interests are acting rationally in the long run. They're protecting their interests in the short term but greatly jeopardizing them in the long term. That's a similar false economy/market failure.