We are pouring huge amounts of energy into the biological effort to understand where life came from, how it arose on planet Earth, because it matters to us; it is, perhaps our deepest question. Really, it boils down to this: Are we special? The best summation has been attributed to the science fiction writer Arthur C. Clarke: "Sometimes I think we're alone in the universe, and sometimes I think we're not," he said. "In either case the idea is quite staggering." Clarke is right. If we are alone, that's extraordinary. If we are not , that's even better. Were we to discover that we are one of many life-forms on a planet that is one of many inhabited worlds, we would have a new perspective on being human - on being alive, even. And if we discover that some of that life beyond Earth is intelligent, a whole new vista of possible human experience opens up before us.
— Michael Brooks
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