Science fiction has long been looked to as a source of prophecy…but why? Perhaps because, out of necessity, its futures work: spaceships fly and inventions are successful because they need to be—there’d be no story without them. And because more often than not (to paraphrase Jules Verne) whatever one man can imagine another one can do, imaginary science often becomes real science. On the other hand, professional scientists have a tendency (and it’s a justifiable one) to be more than a bit conservative—but, as one of Clarke’s Laws tells us, more or less, whenever a venerable and respected scientist tells us that something is impossible, he will almost assuredly be wrong. And that’s exact­ly what has happened, over and over again….