I like to think of myself as a tough-minded intellectual, a foe of all fuzziness from alien abductions to past-life regressions. I hate to think that… - Stephen Jay Gould

Scientists ignorant of history are not so much condemned to repeat it, as to be confused and unenterprising.

Time's arrow of “just history” marks each moment of time with a distinctive brand. But we cannot, in our quest to understand history, be satisfied only with a mark to recognize each moment and a guide to order events in temporal sequence. Uniqueness is the essence of history, but we also crave some underlying generality, some principles of order transcending the distinction of moments—lest we be driven mad by Borges's vision of a new picture every two thousand pages in a book without end. We also need, in short, the immanence of time's cycle.

Our shenanigans, nuclear and otherwise, might easily lead to our own destruction in the foreseeable future. We might take most of the large terrestrial vertebrates with us—a few thousand species at most. We surely cannot extirpate 500,000 species of beetles, though we might make a significant dent. I doubt we could ever substantially touch bacterial diversity. The model organisms cannot be nuked into oblivion, or very much affected by any of our considerable conceivable malfeasances.