"I should say we know that there are many, many other Earths out there. We're almost certain that there will be upwards of a billion Earth-like planets in our galaxy alone, so there is no lack of real estate where life might happen, but what we don't know is how likely it is given the real estate, given a wonderful pristine planet like Earth how likely is it that life will pop up inhabited? We don't know the answer to that."

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I'd say that, in addition to actually taking my brother and sister and I camping and hiking and river rafting all our lives and introducing us to the power of natural landscapes, his [my father's] biggest impact on my thinking has been to always argue that the "spiritual case for Nature" was not going to outweigh the needs of 7 billion people and to insist that law, science and economics were the critical frameworks through which we had to defend the value of nature.

— Edward Norton