No planet is more earth-like than Earth itself, so if life really does pop up readily in earth-like conditions, then surely it should have arisen many times right here on our home planet? And how do we know it didn't? The truth is, nobody has looked.
“When I went in, my editor said, 'I hope you don't think you're a writer.' And I said, 'I hope you don't think I'm a journalist.' And, uh, turned out we were both right.”