In science fiction, the world is always stunningly different. There are flying cars and weird public monorail thingies everywhere. And people have got electronic arms and shit. And there are robots--can't forget about the robots.
And in some parts of this planet, the physical world has changed quite a bit. Today's Mumbai contains things that were almost unknown fifty years ago: malls; skyscrapers; huge numbers of privately-owned automobiles.
But is that really true in America? I would submit, from watching Mad Men, for instance, that the physical world has not changed too much. In fact, given current fashion trends (shorter hemlines; the resurgence of brighter colors), if I was to go back in time to 1963, I'm not sure I'd notice a terrible difference in the world around me. Actually, since that was the high point of urban development in America (before the modern resurgence of middle- and upper-class interest in cities), I'd also submit that today's cities look more like the 1960s (in terms of the relative lack of urban blight) than any point since the 1960s.
Which is to say: life is different, but does it look different? There's a slightly different style in automotive design: they're sleeker and smaller than they were in the 60s. There are no public telephones anymore. There are more electronic billboards and screens. But really there's more similarity than difference. The biggest differences aren't in plain view, they're the computers lurking just out of sight, in peoples' pockets and bags.
And in our visions of the future, this is something that has to give us pause. I do not think, given current trends, that America in fifty years will look terribly different from the way it does today. The pace of technological and economic development has slowed. We are in for an era--perhaps a very long era--of stagnation.
Which has ramifications for our fiction. In Thomas Piketty's book Capital in the Twenty-First Century, there's a fascinating section where he talks about how novelists stopped mentioning specific dollar amounts in fiction. That's because in the 19th century, the economy was fairly stable. There was little inflation. Which meant if you wrote that a person had an income of ten thousand francs, people reading the book in fifty years would still know roughly how much money you meant.
But in the 20th century, that become ridiculous. A household income of ten thousand dollars in 1925 was a fortune; in 1975 it was merely middle-class; and today you'd be beyond impoverished. But perhaps we are once more entering a time of stasis. Perhaps we ought to leave the flying cars and spaceships and silver jumpsuits behind, and instead populate our stories with people who take the train and drive automobiles and wear jeans.
Of course, what fun would that be?