TRANSCRIPT:

It's been famously observed that information lasts forever or for five years -- whichever comes first -- in digital form. I think this is a world we're entering where some people worry about their information lasting forever, and they'd like to leave it behind. Maybe you had a little mistake in your high school years and you got a misdemeanor. You'd like to leave that behind, not have it chase you through life. Or there's that picture of you drunk at a fraternity party.

Other people are dismayed by the fact that stuff they want to preserve will disappear.

Well, in the natural perversity of the world, I think we're going to discover, as we go forward, that the information we most want to preserve will disappear far sooner than we expect. And the information we most want to lose will stay with us for far longer than we could possibly imagine.

So if you're 19 years old today, when you're 50 and you look back, you're going to go, "Darn, I just wish I had that picture of me from my high school prom." But your children, and your grandchildren, and their children will still be laughing themselves silly decades from now of that picture of you acting like a drunk fool at your freshman college party.

That's the kind of dark side stuff. It's not the horrible, end-of-civilization dark side. It's the little embarrassments, the inconveniences and, above all, the unexpected constraints.

Every new technology gives us new freedom, but inevitably, there comes this constraint. Before railroad transportation, passports were virtually unheard of. They were just kind of an exceptional thing. Once we got faster transportation in Europe, countries started putting up barriers and requiring passports. Airplanes give us tremendous freedom, but then we get the TSA and we get body searches and more restrictions on travel. So everything comes with a constraint.