Or: allow population to fall and material prosperity as it is. Note: material prosperity is not the same as living standards, as there is more to life than thin

Or: allow population to fall and material prosperity as it is. Note: material prosperity is not the same as living standards, as there is more to life than things. There is no reason at all to think that 1Bn humans can't live on earth at early 21st C standards more or less indefinitely. 11bn at twice that level.... that's harder to see.