If you believed the germ theory of disease in the 17th century you might find some obscure texts to support you, but mostly you were alone in the wilderness. To stick with that belief in the face of universal scorn, you had to have some really compelling (at least to yourself) evidence.

Most people won’t persist with an unpopular belief. Until late in the 20th century, if your neighbors didn’t share a belief, for most people you might as well be the only person in the world who holds that view.

Today though, you can pick any outlandish theory — the moon program was faked, 9/11 was a government plot, Britney Spears can sing — and you can find more blogs and news sites trumpeting that fact than you can read in a lifetime. Everything is confirmed. No one has to question their assumptions if they don’t want to. And frankly, none of us really want to.

The current media saturation means it’s possible for the first time in history to read only media that confirms your bias, no matter what that bias is.

A one-day $900+ phone bill later, they had a talk with her about her IM-ing habits. I recalled the discussions I’d seen about a teen racking up 14k messages in a single month, and people claiming to have seen twice that.

The math is just astounding, until you realize how they’re doing it: Every kid has a contact group of all their friends, and every IM goes to all of them. They’ve built their own follow lists, and are tweeting constantly.

In other words, teenagers have already routed around Twitter and created a distributed system to solve this use case.

The internet was first used to distribute scientific and academic papers … and porn. It seems man hasn’t changed much in the last few centuries.

The printing press and the internet share some other features. Like the impact they had on society: education, communication, freedom. Plenty of people have written about the similarities. Some have written about the differences. But I haven’t seen much conversation about one important difference: Books can’t be turned off.

Why this matters is that writing is something that can be entirely learned by each person who uses it. There is no risk of being unable to use the technology.

I’ll grant that large-scale printing presses are far beyond the reach of individuals, and even whole cultures. But the base concept of printing is so simple that it could be easily duplicated, and scaled up by anyone with basic mechanical aptitude.

Computation is a whole different animal. The utility of “pervasive computing” is explicitly the pervasiveness. The smart chip in my credit card is useless without a reader. Or a computerized register to attach the reader to. Or an internet connection between the register and the VISA system. Or … or … or …

Look at any major urban blackout. Commerce comes to a complete standstill within minutes. You can literally turn the technology off, and society grinds to a halt.

If you smash a printing press, everyone who already had a book still has it. If you burn all the books, people still know how to write.

But disable the networks that allow us to engage in commerce, and suddenly the grocery store shelves go empty. And we don’t have local farms any more to fall back on.

I’m not suggesting that we’re likely to face a protracted breakdown in the current system. But the impact of such a breakdown is certainly on a new scale.