Thanks for the link! I found Lovelock's perspective as an "optimistic pessimist" interesting:
"I see humans as rather like the first photosynthesisers, which when they first appeared on the planet caused enormous damage by releasing oxygen - a nasty, poisonous gas. It took a long time, but it turned out in the end to be of enormous benefit. I look on humans in much the same light. For the first time in its 3.5 billion years of existence, the planet has an intelligent, communicating species that can consider the whole system and even do things about it. They are not yet bright enough, they have still to evolve quite a way, but they could become a very positive contributor to planetary welfare."
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