The big question for me, that got me started on my current path, is "Where does stuff come from?"  I learned it when I participated in an energy transitions group pre #tightoil  boom.  Take your pick: medical care, mobile phones, food, packaging, etc.  Where stuff comes from needs to be tackled before you answer questions like "Where should it come from?", and "How can we change that?".  #globalsupplychain #food #fossilfuels. And *that* led me to my work on 3SA:

https://zenodo.org/record/7826793