War is an Alien Threat

More than a century ago a young Frenchman, Alexis de Tocqueville, visited America. After that visit he predicted that the two great powers of the future world would be, on one hand, the United States, which would be built, as he said, ``by the plowshare,'' and, on the other, Russia, which would go forward, again, as he said, ``by the sword.'' Yet need it be so? Cannot swords be turned to plowshares? Can we and all nations not live in peace? In our obsession with antagonisms of the moment, we ...

 1847 Speculation About Extraterrestrials

In general I would be cautious against … plays of fancy and would not make way for their reception into scientific astronomy, which must have quite a different character. Laplace's cosmogenic hypotheses belong in that class. Indeed, I do not deny that I sometimes amuse myself in a similar manner, only I would never publish the stuff. My thoughts about the inhabitants of celestial bodies, for example, belong in that category. For my part, I am (contrary to the usual opinion) convinced ... th...

 We Have Announced Our Presence to the Stars

There are those who predict a dire catastrophe if we broadcast our presence to another star. The extraterrestrials will come and – eat us, or something equally unpleasant. (Actually, if we are especially tasty, they need only sample one of us, determine what sequence of our amino acids makes us appetizing, and then reconstruct the relevant proteins on their own planet. The high freightage makes us economically, if not gastronomically, unappetizing.) The message aboard Pioneer 10 was critici...