There’s some back-and-forth at StartUpSkills.com on whether social software will amount to much. Jeremy Zawodny says: “Start thinking about how adding a social networking component to existing systems could improve them.” StartUpSkills replies that people don’t have enough incentive to give away the social network that is their competitive advantage. Personally, I agree with Jeremy that networks such as LinkedIn will only survive if an external application figures out a use for them. Without that, we’re left with people you don’t know asking you to hook them up with other people you don’t know. Om Malik doesn’t understand why people would share their Rolodexes with commercial entities. My problem, though, isn’t that my Rolodex is too valuable to share (hah!), but that social software of the Friendster/LinkedIn sort necessarily get social relationships wrong: First, social relationships aren’t transitive: If A knows B who knows C who knows D, there is no sense in which A knows C much less D. We do, however, have a social convention for first degree relationships: A is entitled to ask B for an introduction to C. But not to D. Second, social relationships aren’t formal (in the logical sense). In logic, if A > B and B > C, then A > C. But — and here’s why people generally don’t name their kids A, B and C — A doesn’t have to ask B’s permission to be greater than C, and C doesn’t get annoyed at B for pestering her with requests from strangers to be greater than C. Every time I introduce someone to my pal C, I am altering my relationship with C just a little bit. Third, real social networks are always implicit. The ones constructed explicitly are always — yes, always — infected with a heavy dose of social bullshit. It’s like thinking that the invitiation list for your wedding actually reflects your circle of friends and relatives. No, you had to invite Barry-the-Boozer because he’s your cousin and you couldn’t invite Marsha because then you’d have to invite her husband Larry-the-Ass-Grabber and her daughter Erin-the-Snot-Flinger. Explicitly constructed social networks not only lack the differentiation that makes relationships real, they are falsehoods built to reinforce spectral relationships and to avoid ending shaky ones. There may be uses for the links created within these artificial social networks, for while the relationships aren’t transitive, some of their properties — interests, tastes, prejudices — are: if A and C both know B, they are statistically more likely to share B’s tastes in music than two randomly selected people are. That may turn out to be useful to some other application. But if you want to get at the real social networks, you’re going to have to figure them out from the paths that actual feet have worn into the actual social carpet. (See Ross on FOAF and Plink and Clay on Om…)