The Standard Issue definition of truth is that truth is a property of statements and that a statement is true if it corresponds to the existing state of affairs. So "The cat is on the mat" is true if the cat is in fact on the mat.
As the Web exposes us to more viewpoints, and as discussion threads end by veering off in new directions rather than by resolving the issues that have been surfaced, "correspondence truth" becomes less and less important. For most of the interesting discussions, there just isn't a knowable state of affairs that could settle the conversational hash. In fact, that's exactly what makes a conversation interesting in the first place. If it's just a quibble over a state of affairs that can be discerned easily, you whip out Guinness or the Britannica, and everyone loses interest.
Truth is a conversation killer.
So, imagine if you will, that you are an author of a book that touts the value of human conversation. And let's say you're talking to a government agency about what should be on its Web site. You're giving your standard rap about enabling the people in the "market" to talk with one another, about networked markets being smarter than the organizations they're talking about and blah blah blah. Facing you are steely eyes who like the idea of conversation but who also know that they are responsible for providing hard, reliable answers.
Yes, they must. While citizens may want to talk amongst themselves and be able to find someone inside the bureaucratic walls who will engage them in frank conversation, ultimately the agency is responsible for giving answers citizens can bank on. But notice that even here truth is not the highest standard. What counts is accountability.
For example, a few years ago a magazine called the IRS help desk 10 times and asked the same question about a tricky item on the 1040 income tax form. It got 10 different answers. Similarly, different tax preparation agencies fill out forms wildly differently even with the same data coming in. What's the right answer? There isn't one until the tax authorities make a decision. Until then, consistency and reliability count for more than truth in the correspondence sense. Only after a decision is made is there an actual state of affairs to which statements can correspond. Only then does truth become the highest value. And at that point it is inextricably bound to notions of responsibility and liability; it gets its force not from some mystical relationship to a state of affairs but to its use in a legal system.
Over all, truth is highly over-valued...except when it refers to the integrity of people in conversation.
David Weinberger is editor of The Journal of Hyperlinked Organization.