I year or so ago I read a couple of SF books by James Halperin. One was called The First Immortal, which is about radical life extension, and I liked it a lot. The other was The Truth Machine, and while it had a lot of intriguing ideas, it was not as well written as it could have been, and I never really bought its premise. It was about a near future world in which no one can lie, because a reliable technology for lie detection has been developed and widely deployed. It mostly explores the social changes that such a technology might lead to (think how this would transform politics!).
My problem with the premise is that lying seems to be a matter of degree. While most people know when they are lying, some don't, and then there is the matter of white lies. Is an insincere compliment a lie or is it something else? Does the context or motivation matter? There are many other issues, of course, and I just couldn't see how truth-telling could really be quantified.
But today I happened to read an article in the January 2006 issue of Wired magazine, "Don't Even Think About Lying." This concerns research and two imminent products based on fMRI brain scans. It seems that lying and truth-telling will "light up" different regions of the brain in distinctive ways, and that these patterns can now be detected. Of course the subject has to be in an expensive, noisy, coffin-like MRI machine, so it isn't exactly an unobtrusive technology. But it apparently works, raising a host of new social, ethical, and legal questions, even before the likely future development into a more "user friendly" interface (wearable or even wireless brain scans?).
Very much like Halperin's The Truth Machine! I think I may have to revisit that book sometime. Truth is stranger than fiction. Lying too.