Science fiction is the source of many of the most popular and immediately recognisable motifs in popular culture. Alongside the ongoing massive popularity of the Star Wars and Star Trek franchises, an abundance of new TV series aspire to their market share. The BBC has brought Doctor Who out of retirement and given him a facelift of special effects, fast (frenetic) paced storylines and thumping incidental music. The result has been almost universally acclaimed. In the last UK census, a sizable percentage of respondents humorously described their religion as ‘Jedi’. Sci-fi is big business.

But what about the two words which form that compound noun? Fiction is the production of stories, about things which did not really happen. And science is the study of the natural world, attempting ever-better descriptions of what does happen. Sci-fi is clearly related to fiction, but how is it different from straight fiction, and what on earth does it have to do with science?

In fact, science and fiction have more in common than may immediately be apparent. And I do not mean that hypotheses can be considered as narratives. Heavens no. Rather, both science and fiction have at their heart the portrayal of a world which operates according to certain laws. At its heart, science is about testing whether laws (or hypotheses if you like) really do govern how the world works. In fiction, one measure of success is how the author’s artificial reality convinces and holds us. Most authors borrow the rules wholesale from the world we live in, but fiction is not short of unfamiliar settings. Indeed, one of the joys of fiction is the opportunity it offers to see the world through different eyes, offering us a tantalising glimpse of another’s consciousness as we inhabit a different world. In some cases, verisimilitude in fiction may be a virtue, but this only matters if the novel claims to be an accurate reflection of a particular milieu. Ultimately though, authors can make their stories up however they like, and provided the book convinces us that it is operating according to internal laws, we are happy with the outcome. Of course there are examples of authors who try to do away with the limitation of confining their story to a single set of rules. But it is fair to say such books are more admired by literary theorists than they are actually read.

In suggesting that, in order to have power, fiction must operate within an imagined world subject to understandable rules, I do not only mean things like gravity, light speed, or eventual death, but also the ways in which human beings respond to events, and societies are structured. It is an interesting point, and one to which I will return, whether these can be changed in the same way as more ‘scientific’ laws.

By altering our perspective, fiction allows us to vicariously experience events we will never encounter in our lives. The astonishing thing about science fiction is that this can be extended to worlds with physical laws different or additional to those which we currently understand. This is done with varying degrees of ambition. Almost any futuristic novel set in deep space contains some speculation about how the problem of travelling at light speed might be overcome. This is a comparatively simple exploration of different possibilities. However, consider a novel like Edwin Abbot’s Flatland, which takes place among beings which can only perceive two spatial dimensions. Such books can tell us something very deep about out relationship with the laws which govern our actual universe. This analysis may be easily extended to include fantasy. Here the rules of the story will often include magic, but magic which is grounded in some sort of system even if that system is not fully explained. Not all authors have been, or need be, as serious as Tolkein with his whole imaginary languages and grammars. But a sort of codification of many such rules can be found in the various role playing games which have sprung up around various science fiction or fantasy adventures.

In general, the distinguishing feature of science fiction is that the imagined world involves additional or different scientific rules. It is striking how few novelists have played around with human culture and social structures. In fact, this seems to be the province of literary fiction. Those science fiction writers who have attempted it are distinguished by their scarcity, and also their quality. Margaret Atwood springs to mind. However, science fiction has often, in a much less ambitious way, expressed contemporary tensions within the societies producing them. A good example is the first interracial kiss on US television, between Uhura and Kirk in Star Trek. More recently, the revival of Dr Who contained a character, Captain Jack, who was clearly bisexual (or at the very least an equal opportunity lech) but yet captured in every other way the archetype of the square jawed action hero. It is in these small ways that sci-fi has generally tinkered with our expectations of human society.

Interestingly, almost all such attempts have centred on human sexual relationships. What are we to make of this? It seems easier for novelists to alter physical laws than cultural expectations. It might be easy to see in this a sort of sociobiological argument for the structure of the societies in which we find ourselves, but I think it is more likely that we would find it very difficult indeed to identify with characters who truly inhabited a human milieu which was very different from our own. After all, we find the thoughts and expectations of the Victorian era shockingly reactionary when compared with our own. Hence such stories just would not sell, and so we do not find them in the bookstore.

Having said that, the majority of the futuristic worlds which novelists have made for us are still unbelievably parochial. If we are seriously interested in using science fiction to explore our humanity and place in the universe, the scientific nature of that humanity has to be up for grabs. The programme of research which calls itself evolutionary psychology is clearly a serious and successful approach to understanding this, even if it is true that some or many of its conclusions should not be accepted at face value: just because an explanation makes reference to natural selection does not mean it is the right one. It is easy, almost ridiculously so, to see Darwinian motivations behind such historical innovations as the chastity belt or droit de seigneur. And although controversial, we can extend similar analyses to modern society.

The impact of changing reproductive technologies on our species is a source of endless speculation but (with the honourable exception of Atwood and a few other trailblazers), novelists’ imaginations have seemed wary of straying from obvious nostrums. This depresses me. Consider that within industrialised societies, we can if we so choose almost entirely divorce sex from reproduction. This already is an enormous change from the worlds of our recent ancestors, and it has created changes in society, dating from roughly the 1960s, which are still in progress. There is no reason to suspect that these changes, despite the best efforts of reactionaries everywhere, will be rolled back. Yet how many writers setting their stories in the near future – let alone the far – are prepared to examine their impact? How much larger tomorrow will be the consequences of novel reproductive technologies in development today?

I do not wish to suggest that no authors have considered these topics, rather that the relish with which they have approached the physical world is conspicuously lacking from treatments of society. I’ve already mentioned Attwood as an exception. J. G. Ballard is another. The French writer Michel Houellebecq has written much in this vein, but for him, the scientific groundings of societal structure in genetics seems to be a source of inspiration for his work, and imposes only a flimsy structure on it. This situation is akin to Graham Greene’s treatment of Catholicism more as a means of keeping score of his sins rather than as a religion.

Over history, we have seen civilisations constructed around human sacrifice on a huge scale, or genital mutilation as a prerequisite for holding a civil service post, or bisexuality as a stage in a young man’s education. This alone should be a reason for writers to explore the variety of ways a culture or society can be constructed, even without the many reasons we might have at the present time for thinking the future will be even more different than the past. Furthermore, by transporting us into such worlds, novelists have a real and important role to play in informing the debate about in what kind of world we want to live. Let us hope for more of this, and less of the laser pistols.