Okay, ugly word. But how many times have you heard this conversation?
degrowther: we should degrow the economy
growther: that would make people's live worse
degrowther: not necessarily! we could reduce our natural resource use while technical progress allows us to transform it into utils more effectively, so that quality of life keeps going up
growther: that's growth dumbass
Somehow, the conversation always seems to stop there (at least in my experience), even though it's where it might start getting useful!
Economic growth can be broken into extensive growth (more people and natural resources) and intensive growth (better technology lets us do more with the same factor inputs.) So what the soi-disant degrowther is arguing for is disextensification.
Is disextensification desireable? This intersects with more targetted questions like:
How much can extensive and intensive growth be decoupled? (In a Malthusian model they are inversely related; in an endogenous growth model they're closely related)
What kinds of ecological limits on our civilization are we running up against?
What level of intensive/TFP growth can we expect such that total per capita growth remains positive, if we were to experience disextensification?
Does it make sense to think about total extensive use overall, or does it make more sense to just take particular cases of land use, etc, that may have undesirable effects and balance those against their economic gains? (Maybe turning rainforest into cattle raising is net negative, but turning grasslands into wheat fields is net positive.)
I have intuitions on all of these, especially (4), but not firm answers.
(Some deep green types might say "fuck it, burn it all down" on semi-deontological grounds, and as with their counterparts e/acc I really can see where the intuition is coming from, but as with e/acc I can't go there because I love humanity and want the human project to continue.)