In The Moral Landscape: How Science Can Determine Human Values, Sam Harris raises the possibility of an accurate lie detector based on neural imaging: a machine that could accurately determine whether a statement someone makes accurately reflects their belief on the matter at hand.
Harris discusses the social consequences of the existence of such a machine, and generally thinks they would be positive. They would, for instance, reduce the number of false convictions and false acquittals in the criminal justice system.
Personally, I think the social and cultural effects of such a machine would be extremely widespread, if there was general confidence in its accuracy. Inevitably, there would be calls to test how genuinely all sorts of people feel about things. Does this proposed Catholic bishop really believe in key elements of Catholic doctrine? Does this politician honestly intend to fulfill a particular promise? Does the man who just proposed marriage to a woman really think she is the most beautiful woman he has seen? Does he really want children? Does he really intend to stay with her into old age? Has be been entirely faithful during their courtship? Would he have taken the opportunity to sleep with someone else, if it had arisen?
Of course, the machine could then be turned on the other partner.
If it ever became culturally acceptable to subject people to impartial evaluation on these sorts of questions, it would have countless direct and indirect effects. For one thing, I think it would make hapless pawns more important. Rather than having cynical mob lawyers who know all about the family’s murders but exploit the legal system in every possible way regardless, there would need to be a lot more ignorant people defending important individuals and institutions. Similarly, corporate CEOs would no longer be able to hedge strategically to avoid liability, which could significantly affect the safety and availability of many products in the long-term. For instance, people would have a lot more trouble selling placebos as medicine.
To a large extent, I think society is based around the general acceptance of various kinds of lies. If the people who ran or represented the world’s governments, churches, and corporations had to be scrupulously truthful at all times, the public understanding of how the world operates would change radically. I don’t think this is because people are terribly ignorant about reality. More it is because there are many deceptions which we are comfortable with accepting. For instance, that we are already doing an adequate amount to help those who are starving around the world; that our governments do not commit war crimes or contribute to genocides; that our meat doesn’t get produced in exceptionally cruel ways; and so forth.
There would also be small-scale consequences. To me, it seems that politeness is fundamentally bound up with deception. At the very least, ‘being polite’ requires withholding genuinely held beliefs that would be offensive to other parties in a conversation. At most, it requires actively lying to them. The existence of an effective and credible lie detector would strip people of the ability to be polite. It is possible that would be liberating – allowing people to really express themselves without fear, and granting a better perspective into the real thoughts of others. It is also possible it would be devastating: breaking up businesses, families, and long-standing marriages when people learn things that they simply cannot handle – especially with the full knowledge that they are true (or as much confidence as the accuracy of the equipment allows).
All this relates to some of the issues raised by the film The Invention of Lying, which I commented on before. To have any hope of surviving in this world, we need to be able to accept the possibility that a person could be wrong about something. When someone says that the elevator has arrived, we check before stepping through the open doors into the elevator shaft. Even a perfect lie detector would do nothing to protect us from honestly mistaken beliefs. What it would probably do is have profound social and cultural effects, as a huge number of people found themselves in a position where they either had to submit to the test or foster the widespread view that they aren’t genuine in the claims they are making.