There is no single optimum, however there is value beyond merely surviving. Our quality of life is better than it was in the past, so why would anyone be happy at the prospect of that going down due to climate change?
True, it shouldn't be survival for its own sake. But do we really believe that our quality of life will be going down because of (some, warmer or glacial) climate change? how soon does that happen, and is humanity powerless to adapt? I have a very optimistic view of human potential, I think in essence and the long term all problems can be solved.
Does the fact that CO2 levels have varied hugely in Geologic Time affirm that we are under imminent threat of terrible climate changes? is it irrelevant? or contradictory? or a puzzle? is it impolitick to ask such questions?
Does the fact that CO2 levels have varied hugely in Geologic Time affirm that we are under imminent threat of terrible climate changes? is it irrelevant? or contradictory? or a puzzle? is it impolitick to ask such questions?