In many business/financial situations, correct but deceptive answers are possible.

It seems likely that any lie detection device based on brain states will actually detect intent to deceive, and not lies per se.

I don’t know that it would generate quite as much trust as suggested. Politicians, for instance, are very good at evading inconvenient questions. In many business/financial situations, correct but deceptive answers are possible.

But it would have very radical effects on the criminal justice system. It would make it far easier to solve the great majority of crimes, with benefits to the innocent suspect as well as the authorities.

Even a fairly expensive hat-of-truth would pay for itself.

Of course there are questions about what it could actually measure – many people self-deceive, or simply are mistaken. Children as witnesses are always problematic, even when it assumed they aren’t lying.

Still, a device that could detect conscious deception would be worth a lot.

I’m at a loss as to why you see this as troubling. Aren’t deep brain scans precisely what’s needed for full-brain emulation? The only troubling aspect I see is our biases in interpreting the data into clear cut categories, like Robin was saying.

Aaron

by refusing to put one on you’d be admitting you expected to lie

Aren’t you dismissing the full game-theoretic possibilities here? Those of us who cooperate against such a technology will always refuse to don the truth hat. By our own action, we reduce the certainty of such a conclusion proportional to the number of us that cooperate. I am my own existence proof of someone who would unconditionally refuse the hat (subject, of course, to sufficiently extreme coercion), so I expect at least a few others to cooperate.

“friends should usually be trustworthy on things you can easily check, but should be tempted to be otherwise when checking is rare or takes a long time. On those topics, it should be hard to tell if they are trustworthy or not.”

I have thought about trust for a long time and have read several books on trust (like Fukuyama) and also game theory. Indeed, Chris Hibbert and I have talked about this.

Credibility can be built in 9 ways, I posit: establish a reputation for trustworthiness & then use it; develop your reputation through teamwork with the other party; rely on a mutually trusted intermediary to vouch for your reputation; move in small steps at the start, then larger and larger ones to cement your reputation; destroy your own retreats; post collateral; voluntarily deprive yourself of valuable information first by sharing information; when all else fails, write contracts.

High trust usually returns high trust, at least in high trust societies, which the US isn’t anymore. Still, I always start with high trust. I found this highly effective in the UK, for example, where there is still the idea of real manners. Publicans will take the opportunity to be a “true English gentleman” when offered.

I have personally found that by being open to people first, they are more likely to respond “better” because they want to think of themselves as “nice.” Then, when they are nice, praise them for their niceness. Tell them they are more trustworthy than others. This accords with what most people already think of themselves (we’re all above average, right? the Lake Wobegone bias).

By confirming their own beliefs, they like you even more and offer you increased reliability because they are loathe to destroy their own sense of being nice and being above average. Reinforce by occasionally telling them stories of your other horrible acquaintances who aren’t as nice and trustworthy as they are – this raises their sense of relative status, which is how people usually judge themselves. Rinse and repeat.

Once we understand what our common biases are, we can use some of them successfully to help ourselves and other people too! By the way, I have often wondered if one of the many purposes of gossip is to serve as a tool of the kind of checking Robin mentions. I may not personally be able to check X, but someone on the grapevine may have, so we all spread information for verification purposes?