Imagine for a moment, if you will, a piece of science fiction written and published today. It focusses on the problems of ecology facing the world. It's up-front with its message: we need to do something about global warming now or we'll lose the lowlands of the world, and all the species they are home to.
Now imagine that same piece of science fiction thirty years in the future, in a future where worries of global warming have been eased - at least in terms of icecaps melting and raising sea levels - because of a series of dykes that have been raised the world over by pioneering Dutch engineers. The story becomes dated and easy to place - the second decade of the twenty-first century. It loses relevance. It may be a classic of its type, but there's every chance that it'll be forgotten and drowned beneath the tidal wave of new fiction concentrating on other contemporary problems, which in turn will be swept away by subsequent fiction of the same sort.
So how do you make sure a story set in its time remains relevant?
I would argue that the answer can only be found in fiction that doesn't tackle issues head-on - but tackles them through its cast of characters. Take Frank Herbert's Dune, for instance. I'm going to come clean and say that it's one of my favourite books, not least because I'm in love with the story (so I may be a little biased). I'm also going to say I'm not going to waste time and talk about the heavy-handed and over-preachy sequels written by either Frank or his son, Brian. If you want to read them, be my guest, but don't expect them to measure up to the magnificence of the original.
Dune was first published in 1965 and isn't about ecology - but it so easily could have been. It could also have been about resource wars, and I have no doubt that were it released today it would be taken as commentary on American foreign policy in the Middle East. And it's not really about resource wars either. What Dune is about is people - in particular, politics and religion, and often how those two combine. This may as well be explained in the first chapter, as Reverend Mother Gaius Helen Mohiam of the Bene Gesserit Sisterhood demonstrates the purpose of her order to Paul Atreides, Ducal heir and protagonist. As time goes on, Paul moves with his House to Arrakis, the only place in the universe where the spice Melange may be found, a desert planet with a savage climate. The family are put there by their ruler, and they find themselves engaged in vendetta with the Harkonnens, holders of the previous fief over the planet, who mined spice and provided the universe with its most precious commodity.
All I mentioned above - ecology in particular - form part of the background themes of the novel, but because of the vendetta and the politics that take place as a result of it and subsequent manoeuvrings the focus is forced onto the people - and more specifically, onto how those people react and behave and react to events around them.
People are the one perpetual truth in society and literature. Everything in life comes back to humanity and what's best for it. Even the biggest themes in literature - such as the old Arthur C. Clarke favourite of the human race's place in the universe - have the human element. But things relating to humanity change, while humanity does not. The world moves on while mankind exists in perpetuity. Mankind's invented interests - politics not least among them - travel with humanity like a second skin, unlike the events we react to such as global warming (see: ecology).
And this is what Dune is best at. It distils everything to a human level. And because it's not tied to its non-human themes, it means it can continue to be relevant.
If I were to go on and talk about how only science fiction can really do this (as other forms of literature are tethered to their time of writing in many ways) I'd be able to make a fair case. But it isn't one for today. My point has to be that the human side of writing is more important than the contextual side - one is a constant and this has to be remembered.