If I never hear the phrase "self-selector" or "digital commons" again, it will be too soon. But for better or worse, they embody two of the most important principles in my work. The digital commons is the hypothetical virtual space (yes, hypothetical and virtual) in which people of different backgrounds, beliefs and political persuasions encounter each other. It is the public sphere the Internet supposedly makes possible, in which we can live out what sociologist Ray Oldenburg calls our "informal public lives." Self-selection comes up any time we talk about getting a large group of general-interest citizens together online. How do you attract the people not already inclined to join forums, engage in policy dialogue, or just visit your new web site? Today, NYT's Amy Harmon wrote about how self-selection online makes the digital commons unlikely to come to fruition. Instead, the article argues, "cyberbalkanization" is fragmenting the online population…

Got this note from my buddy Miriam Rabkin, a doctor who's on the ground in Maputo, Mozambique this week: When I started this weird type of travel, it seemed as though our world - email, iPods, taxis - was the real world and this was 'elsewhere.' But how can our world be the real world when so few people live in it? There are hundreds of millions of people here. This - constrained lives and lost opportunity; flame trees glowing over heaps of garbage; despair and laughing children - this is how most people live and die. It's not romantic or exotic. It's just the way it is. She's in Africa regularly working on the MTCT-Plus program. MTCT is Mother-to-Child-Transmission of HIV. Remind me not to sweat it next time I get a relaying error trying to send email.

Since the surprises of the Iowa caucus, positivity is getting some positive press. After his shocking second-place showing, Sen. John Edwards told supporters "America was not built by cynics, America was built by optimists." Corny, but nice to hear nonetheless. That night on CNN, James Carville apparently praised Edwards as the best stump speaker he's ever seen, including Bill Clinton. (That was shortly before right-wing pundit and personality Ben Stein called Edwards "The Breck Girl.") Howard Dean has a hard time being positive. Or maybe a hard time not being negative. Or maybe he's just a man of his time and the mobilized base up til now has been the bitter base, the people who didn't want a war, don't like the feeling they're being watched and don't think the man in the White House is their duly elected leader. Whatever the history, Dean is now facing the cost of…