As security concerns mount, networks proliferate and ever more data move online, personal privacy and anonymity are often the first casualties. For the Insights story, "A Little Privacy, Please," appearing in the August 2007 issue of Scientific American, Chip Walter sat down with Carnegie Mellon computer scientist Latanya Sweeney, who discusses the new threats to privacy and ways to fight identity theft and other misuse of information.
Why is privacy versus security becoming such a problem? Why should we even care?
(Laughs) Well, one issue is we need privacy. I don't mean political issues. We literally can't live in a society without it. Even in nature animals have to have some kind of secrecy to operate. For example, imagine a lion that sees a deer down at a lake and it can't let the deer know he's there or [the deer] might get a head start on him. And he doesn't want to announce to the other lions [what he has found] because that creates competition. There's a primal need for secrecy so we can achieve our goals.
Privacy also allows an individual the opportunity to grow and make mistakes and really develop in a way you can't do in the absence of privacy, where there's no forgiving and everyone knows what everyone else is doing. There was a time when you could mess up on the east coast and go to the west coast and start over again. That kind of philosophy was revealed in a lot of things we did. In bankruptcy, for example. The idea was, you screwed up, but you got to start over again. With today's technology, though, you basically get a record from birth to grave and there's no forgiveness. And so as a result we need technology that will preserve our privacy.
How did you get into this line of work? What drew you to mathematics and computer science?
When I was a kid [in about third or fourth grade], one of my earliest memories, was wanting to build a black box that could learn as fast as I could. We could learn together, or it could teach me. I wanted the sort of teaching-learning experience that could go as fast and as deep as I could go.
What triggered this black box fantasy?
In hindsight, I think I was bored in school, because I would finish the assignments and would have to wait for the rest of the class. I think it was an outlet and I began spending hours fantasizing about this box. It [eventually] became a real passion ¿ so when I went on to high school and took my first computer course that childhood vision and this sort of natural interest with computer programming just melded together .
After high school, you went to M.I.T. How did it feel being one of the few girls in a predominantly male college?
I first went to M.I.T. in 1977. But it was a tough adjustment. I came from a top-notch prep school for girls and going from that environment to M.I.T.--well, it's almost impossible to be more opposite, in every possible way. It was huge, it was in the city, I couldn't sleep it was [so] loud. Oh man.
But the thing that really made it hard for me was the faculty; I had a lot of incidents with the faculty that were really obnoxious.
What kind of obnoxious incidents are you talking about?
The way M.I.T. is structured is that in your freshman year the lectures are in huge halls with over 100 students, and then you go into smaller groups on the same subject that had only 10 to 12 students. Every week there were 10 problems in a problem set. So the guys [in our group] came to me and said "look we're going to start a study group' and I said, "what's a study group?" And they said, "well, every week we're going to get 10 problems, and every week one of us will get assigned a problem and the day before the homework is due, we'll all meet and your job is to tell the rest of the group your solution and then they don't copy it down, you explain it to them and they go write it up themselves, or if we don't think that's the right solution, we'll discuss it." And I said, "Oh okay. That sounds good to me."