Nevertheless, transparency is generally a good thing. In fact, it's what the philosophers call a prima facie good: You don't need a justification to be transparent, but you do to be not transparent.

So why is transparency only now the "In virtue," the one written on the lunch boxes the cool kids carry? Thanks to the Internet, customers and citizens can see through companies and politicians. We're talking with one another about the products we buy, and we're telling one another the truth. Your business is already transparent -- Haha, we can see your underwear! -- so you might as well embrace it and claim it was your intention all along.

Transparency doesn't travel alone. By embracing transparency, a company makes some implicit statements: We have nothing to hide. We trust you enough to give you information that we used to keep secret. We're not going to try to snow you (any more). We are honest. We deserve your trust. We're okay with being seen as fallible mortals. We are good people.

And it goes beyond making a small change in the tone of PR. The promise of transparency is that the customer is being put into a new relationship. Instead of treating customers as couch potatoes bred to be bathed in the hostile photons of marketing messages, we're going to assume we're all adults. We're going to do our business as if it were a matter of mutual benefit. No trickery, no hype, just quickly coming to agreement about what's in each of our self interest.

Of course, saying you're transparent and being transparent are different things. A company can think it's being transparent because it's releasing information and because it's allowing employees to blog about the business' inner life, but subtle and not-so-subtle forces can turn transparency opaque, or at least translucent. For example, management body language can tell employees that if they blog anything except happy face news, they may not do so well in their next performance review. Or, the company may decide to keep some information classified not because it's truly secret but because it would show the company in a less than flattering light. Because no one insists on absolute transparency, which would include installing webcams in the executive bathrooms, it's always a matter of degree, and that leaves open the possibility that companies will think they're being transparent enough because they're letting customers peek through the peep hole, when transparency requires at least leaving the blinds up now and then.

So, transparency is generally a good thing, even if it isn't an absolute. It is especially good -- in fact, it's becoming a requirement -- in those elements of the business most used to subterfuge and manipulation. (Hint: Marketing and PR.) In a culture built by open and honest conversation among customers, techniques such as astroturfing are especially despicable because they abrade trust. It's bad enough when messages from people within the business pretend to be personal when they're in fact written by the PR department or generated by marketing bots. We've learned to expect such communications to be lies. It's far worse when messages purporting to come from customers are lies because now we can't even trust one another.

So, all hail transparency... except...

...Except it's important that we preserve some shadows. Opaqueness in the form of anonymity protects whistleblowers and dissidents, women being beaten by their husbands, girls looking for abortion advice, people working through feelings of shame about who they are, and more. Anonymity and pseudonymity allow people to participate on the Web who perhaps aren't as self-confident as the loudest voices we hear there. It's even been known to enable snarky bloggers to comment archly on their industry, even if sometimes they play too rough.

Likewise, some meetings should be held behind closed doors. Privacy can be liberating. There are some things we're not entitled to know and some activities are better with the lights off.

Sure, there are abusers, but personal anonymity is the default in the real world -- if you live in a large town, not only don't you know everyone you see, but you're not allowed randomly to demand ID from them -- and it ought to be the default on line. The top-down demand for strong digital ID, which sounds good on paper, is likely to flip the default to the peril of political freedom, the growth of new social forms, and the liberating sense of personal play. Transparency is a prima facie good for institutions, but we individuals are more complex than that.

So, the mood of transparency sweeping through business is healthy and important. Unlike fairness, transparency is not a good in itself. We need to use it with our eyes wide open.