One evening this spring, I attended an event at Trader Vic's in Palo Alto, sponsored by the Commonwealth Club of California. The topic was social networking, a subject that members of the club were predisposed to be interested in, since, although it bills itself as a "public affairs group," the Commonwealth Club is really an old-school social network.

The panelists that night included Jas Dhillon, CEO of ZeroDegrees.com, recently purchased by Barry Diller's Interactive Corp.; Stanford sociologist Mark Granovetter, whose 1973 paper "The Strength of Weak Ties" is a foundational document in the young discipline of networking science; Ben Smith, CEO of Spoke.com, which provides social networking services to corporations; and Valerie Syme, executive vice president of Tribe.net, a company that aims to employ social networking as a tool for the delivery of local online classified ads.

A posting on Tribe.net had led me here. I found out about the event after joining a "tribe" called "social software intellectuals" -- originally created by Marc Canter. A tribe, on Tribe.net, is what would be called a "group" or a "conference" or a "forum" on other community sites. Tribe.net is part of the second generation of social software networking sites (along with LinkedIn, Orkut, MySpace and others) founded by people who witnessed the explosive growth of Friendster in 2003 and wanted a piece of the action. (The founders of both Tribe.net and LinkedIn were early investors in Friendster.)

If you join a tribe, notice of relevant events to that group will be posted on your Tribe.net home page. It's a simple, intuitively useful idea. Who wouldn't like to be able to check their home page and be spontaneously informed of local events of interest, as recommended by your friends, or even as advertised to the specific communities you've chosen to join? Your network becomes your filter on the world, and the more carefully you cultivate and nurture that network, the better the filter becomes.

At Trader Vic's, the audience had come for some clarity, but arrived armed with skepticism. For some Silicon Valley veterans, their carefully and painstakingly accumulated personal networks were their stock in trade, their competitive edge; why should they lay them out for all to see on the Web? For others, burned one too many times before by venture capital-spawned fool's gold rushes, social networking sounded like the latest sucker's pitch. To still others, the whole idea of linking up with friends -- complete with a picture showing you to your best advantage and a profile calculated to make you look cool -- seemed distastefully high-schoolish. On Orkut and elsewhere, random strangers were asking others to be friends on the flimsiest of bases. I read your blog, can I be your friend? Like you, I'm a Yeah Yeah Yeahs fan, can I be your friend?

But the not-so-secret secret of social networking is that flimsy is good! Flimsy is where the action is. Seek out flimsy, and you shall be rewarded. As Mark Granovetter explained, for what must have been the thousandth time this year, the counterintuitive key to social networking is that its value doesn't inhere in linking up to your best friends and soul mates. You are far more likely, argued Granovetter, to find leads on a good job or a prospective date from the networks of people you don't know very well.

You are already probably familiar with the friends of your best friend, or spouse, or close office colleague. There's no fresh territory to plunder there. It's those people with whom you have "weak ties" -- the vague acquaintances, that guy or gal you once kind of knew, a little bit -- who offer a path into possibility that you didn't know was there. The essence of social software networks is that they are a clever way to organize access to the networks of people you aren't actually friends with.

People, especially in the business world, especially salespeople, have been trying to figure out how to do this forever. But it's a tough problem, because once you start dealing with a network that consists of the friends of the friends of your friends, you are confronting big numbers and big complexity. I have 50 "friends" on Orkut -- my resulting network has 410,000 members, and is growing by 20,000 every week!

The human mind is not built to deal with networks that large. But computers make it easy. As sociologist Duncan Watts argues in "Six Degrees: The Science of a Connected Age," serious research into network theory wasn't really feasible until the development of fast, powerful computers. Doing the math involved was simply too arduous.

In the past, the supernetworkers, the salespeople with the fat Rolodexes and the eidetic memory of names and faces, were exceptional cases. But today, creating an online Rolodex has never been easier. Point and click a few times, and boom, not only do you have a little network of your own, but you can suddenly browse through the hundreds of thousands of people you are linked to. Keeping all those hordes of almost-but-not-quite-complete strangers organized is a snap.

But if you can keep track of all those strangers, they can also keep track of you.

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