I recently ran across this interesting article about Radical Honesty, a movement founded by a psychotherapist named Brad Blanton who suggests that we should kick our addiction to lying and just tell the complete truth all the time. I also like this quote from the Wikipedia article on Radical Honesty: "The significant majority of participants in the Radical Honesty workshops report dramatic changes in their lives after taking the course, though they are not always comfortable and positive." The movement visibly suffers from having been founded by a psychotherapist - it's more about the amazing happiness that absolute truth-telling can bring to your relationships (!!) rather than such rationalist values as seeking truth by teaching yourself a habit of honesty, or not wishing to deceive others because it infringes on their autonomy.
I once suggested a notion called "Crocker's Rules", which was the mirror image of Radical Honesty - rather than telling the whole truth to other people, you would strive to always allow others to tell you the complete truth without being offended.
Crocker's Rules didn't give you the right to say anything offensive, but other people could say potentially offensive things to you, and it was your responsibility not to be offended. This was surprisingly hard to explain to people; many people would read the careful explanation and hear, "Crocker's Rules mean you can say offensive things to other people."
I was initially a bit suspicious of Blanton's movement - it seemed like the mirror-image that so many people misinterpreted, the option of saying offensive things to other people. But Blanton makes it not only optional, but mandatory to speak your mind - a far greater inconvenience than Crocker's Rules would ever impose on anyone.
Crocker's Rules didn't catch on. Maybe it was too hard to tell the difference between someone delivering a slap in the face, and someone deliberately invoking Crocker's Rules - you don't want to miss a real clue to real hostility because of your acceptance; you wouldn't want to not believe a true fact, even if the true fact is that someone else hates you. And third parties may assume the truthteller is an offensive person no matter how much the receiver disclaims offense - they may assume the receiver is "just being polite", or that requesting honesty does not excuse its offensiveness.
Will Blanton's Rules ever catch on? I worry that Radical Honesty would selectively disadvantage rationalists in human relationships. Broadcasting your opinions is much easier when you can deceive yourself about anything you'd feel uncomfortable saying to others. I wonder whether practitioners of Radical Honesty tend to become more adept at self-deception, as they stop being able to tell white lies or admit private thoughts to themselves. I have taken a less restrictive kind of honesty upon myself - to avoid statements that are literally false - and I know that this becomes more and more difficult, more and more of a disadvantage, as I deceive myself less and less.
I suspect that the neural circuits that we use to lie to others, also censor our own thoughts. Honesty to others is important unto a rationalist, even one who is seeking a strictly selfish advantage in finding truth only for themselves. If there were a Bayesian Order, would its practitioners take a vow of Radical Honesty?
I think that if there is ever a vow of honesty among rationalists, it will be restricted in scope. Normally, perhaps, you would avoid making statements that were literally false, and be ready to accept brutal honesty from anyone who first said "Crocker's Rules". Maybe you would be Radically Honest, but only with others who had taken a vow of Radical Honesty, and who understood the trust required to tell someone the truth.
Maybe Radical Honesty would be reserved for matters sacred unto a rationalist? In some domains this is already the case. We believe that scientists should always tell the whole truth about science. It's one thing to lie in everyday life, lie to your boss, lie to the police, lie to your lover; but whoever lies in a journal article is guilty of utter heresy and will be excommunicated.
I wonder what it would be like to have anyone in the world, even a single person, who you could absolutely trust. Or what it would be like for there to be anyone in the world, even a single person, whom you had to tell all your thoughts, without possibility of concealment.
This came to mind: http://xkcd.com/69/