vice Benner Cho is a human who has been turned by the Ariekei into a simile. While you take a moment to recall instances where this is possible (the boy who cried 'wolf', Quisling) imagine a language where it is impossible to lie or describe that which doesn't exist. One where the word 'imagine' has no place. This is the Language of the Ariekei, for whom there is no difference between the word and its referent. When comparisons are necessary they must have humans enact an action in order to allow themselves a simile. When the Ariekei speak, they speak with two mouths.

China Miéville's ninth novel, Embassytown, is set on the distant world of Arieka on the edge of the universe. The beings native to the planet – the Ariekei – are, interestingly enough, unimaginable despite all the tricks of language at Miéville's disposal: and that is perhaps part of the point in a book that is entirely about language and often about the politics of it.

When Avice – who is an 'immerser' or space traveller – returns to Embassytown with her linguist husband Scile, the place is on the cusp of immense and disastrous change. The colony's leaders are the Ambassadors, who are humans genetically modified in order to be able to communicate with the Ariekei. They are clones, speaking simultaneously, which is the only way the Ariekei understand humans when they speak Language. A new Ambassador has been sent by Bremen – the empire Embassytown nominally represents – whose effect on the Ariekei is catastrophic. What follows is the collapse of a language, of communication and of a whole society.

Via Plato, Saussure, and Wittgenstein, Miéville examines the nature of language, how it is spoken and understood, and what its relationship with power is. Embassytown is full of arguments and theory but this fuels the story rather than distracts from it, because Miéville does what he began to do in his previous book, Kraken: he literalises abstractions. So the Immer is both an actual medium through which to navigate space and a metaphor for language itself: "Immer is what underlies or overlies, infuses, is a foundation, is langue of which our actuality is a parole", Avice explains.

So also the idea that the Ariekene Language is not-two – sound and sense not separate – finds an analogue in the double-voiced Ariekei (who, though equi-vocal, cannot lie) and the Ambassadors who try to mimic their forms of speech: they also are not-two. Even the Ambassador's names – CalVin, EzRa – conveys the more complex idea of non-duality. If, like Scile, you admit the presence of a soul, the Ariekei could be the whole beings of Plato's Symposium, whose cleaving is at once disastrous and a kind of freedom.

The beings native to the planet are unimaginable despite all the tricks of language at Miéville’s disposal: and that is perhaps part of the point in a book that is entirely about language and often about the politics of it.

The process of untethering the language from its pristine state of non-duality is one that Scile sees as an act of evil. "That's what we do. That's what we call 'reason', that exchange, metaphor. That lying. The world becomes a lie."

his urge of the outsider to preserve or change, exploit or encourage, is what takes the novel into an examination of imperialism. In the beginning, the residents of Embassytown are respectful of the Ariekei, whom they call Hosts. By the end, the Embassytowners have become the source of the Ariekei's resentful sustenance and have managed to command their obedience whilst infantilising them.

One of the most discomfiting things about the book is Avice's apparent complicity in the actions of the Embassytowners as they take it upon themselves to bring order into the chaos their Ambassador has wrought. When one Ambassador orders tests to be conducted on a captured Ariekei, Avice says, "They gave us a dirty hope. It was one of the most selfless things I've ever seen." But Avice's presence as committee member gives us a ringside view of the workings of a hungry empire, and its justifications for its actions. It also makes her later choices more satisfying as narrative.

Avice is a self-conscious narrator, occasionally addressing the reader directly. This could become a tricky device with which to navigate the story, but Miéville just manages to pull it off because he gives his narrator the awareness that structure, metaphor, language, is necessary to the telling of a good story, whether true or not. It is the 'equivocation of the fiend that lies like truth' but it is also the medium through which the world can be thought about differently and be reshaped, a way to 'tell the truth best by becoming lies'.

I sometimes found myself wishing, though, that Miéville himself had found a finer balance between language as the engine of the plot and language used for the sheer joy of it. To use his own metaphor, he could have immersed himself in the language more while continuing to navigate with it.

All the same, it should no longer be necessary to describe China Miéville as a writer to watch, as if his talent and ingenuity were in doubt. Call him, rather, a writer to whose work one looks forward with anticipation and reads with pleasure when it arrives.