I've had more than one argument, mostly with people at school, about whether there's something inherently wrong with lying. My argument is, essentially, that there's no way to have a conversation without lying. That language is lying. China Miéville's Embassytown makes this case brilliantly, by way of comparison. It takes place, in the near-unfathomably distant future, on a fringe planet at the edge of charted space. There, humanity manages through rigid formality to coexist with the sentient species native to the planet, the Hosts, who speak Language (note the capitalization) -- which requires two voices to speak. The Hosts aren't able to lie. For them, thought and speech are indistinguishable. Language contains only truth.
The viewpoint character of the book is Avice Benner Cho, a native to Embassytown (the human city on the planet) who is a simile in Language. That means that she was chosen as a child to perform a series of actions, while Hosts watched, so that they could speak her -- use the fact of her existence, and the fact of her past actions, as a simile to convey other thoughts.
Embassytown is the easiest Miéville book I've read so far -- it's far less thick and twisting than Perdido Street Station, or at least more focused and less fantastic, so it's easier to keep track of things. And the alien-ness of the book is, while perhaps more alien, at least more straightforward than in The City and The City. Or maybe I'm just getting more used to reading Miéville's work.