"What is truth?" asked Pontius Pilate at one of the more consequential moments in human history.
It is a question that persists in our own time, which might reasonably be called "the age of the lie." If every major institution is a crystallization of the dominant values of a society, what are we to think about the latest news from the world of sports?
Floyd Landis' recent win in the Tour de France has been overturned by a drug test. Justin Gatlin, reigning Olympic champion in the 100 meters, faces a possible lifetime ban from the sport after testing positive for testosterone. The spectacle of bulked-up major league ballplayers denying steroid use has become familiar.
The world of literature has given us (among others) the fictional memoirs of James Frey, T. "Nasdijj" Barrus, and Savannah "JT Leroy" Knoop. Journalists Jayson Blair, Stephen Glass and Jack Kelley have done their share to create skepticism about the accuracy of our newspapers and magazines.
A lot of space on the Internet is now devoted to manufacturing identities. Whether in chat rooms, on social Web sites or in areas devoted to the search for love, the "profiles" that people create are the subjects of widespread and justifiable disbelief. How many friends can you accumulate on MySpace.com? Are they really your friends?
Is it essential in evaluating the work of a filmmaker who makes religious movies to know that he is anti-Semitic? One would think so, but can we find out the truth by asking him? Apparently not.
Then there is the government. No administration since Richard Nixon's has done as much to undermine confidence in its public pronouncements ("You're doing a heckuva job, Brownie").
Is any of this important? We have always been subject to deceit for profit or power. Who among us has not lied when it suited our purposes? Why should we care when public figures play us for fools?
One answer is that, confronted with threats to our way of life, even our very existence, we can only respond correctly by apprehending the truth. Put another way, we are continually using our experience to create in our heads a map of the world and how it works. If our maps are inaccurate, it will be impossible for us to navigate correctly, to make sound decisions about our lives and our society.
We would do well to stop believing in astrology, miracle cures, and versions of religion that foster an illusion of exclusivity, because adherents of such theologies tend to occupy themselves with coercive fantasies unsuited to a free society. The worst of them would kill us if they can't convert us.
There is a school of thought that truth is a flexible construct, elusive and subject to interpretation. In at least one area, this is demonstrably not the case. Nature and its laws are intolerant of fools. I thought of this last year while watching the documentary Grizzly Man. When Timothy Treadwell chose to live among the Alaskan grizzlies for extended periods, he imagined that they reciprocated the affection and respect that he felt for them. He gave them names. It turned out, of course, that while he was indulging his naive delusions about these wild creatures, they had also given him a name. That name was "food," and his life was ended by a hungry bear.
A second disadvantage of public lies is that they erode the trust that enables us to live peacefully with each other. We need to have some reasonable expectation that our news is accurate and our leaders are being honest with us in order to have a functioning society. Imagine what driving would be like if we could not trust our fellow motorists to stop at red lights and to drive on the right. There can be no governing consensus and no enforceable law without a shared sense of trust. Every time one of our major institutions, especially our government, lies to us, there is a slight but progressive erosion in our ability to rely on each other. As with the "inconvenient truth" of global warming, we may end up drowning in a flood of cynicism and distrust.
If we believe that in most areas the truth exists in some discernible form, then we must demand it, first from ourselves and then from those we depend on to help us construct a map that will lead us out of the thicket of lies in which we find ourselves.
Gordon Livingston, a psychiatrist who lives in Columbia, is the author of "And Never Stop Dancing." His e-mail is email@example.com.