How much non-renewable and renewable materials do we have?
Scarcity steadily increases and the even renewable materials have thresholds. Cutting down trees will at a certain point/amount lead to erosion and collapse of the ecosystem with no more trees being able to grow. Space is also a limiting factor. For a crops to grow, it needs a lot of things, but one profound requirement is space to grow.
Finitude is even more apparent in non-renewable materials like minerals. There is the possibility of reuse and recycle but 1st and 2nd law of thermodynamics will always pose the question of limit to us.
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