Want a scapegoat for the economic crisis? Mark Zuckerberg looks pretty good right now. Facebook's young CEO dreams of a world where we instantly know each others' emotions. To our peril, we're already pretty close.

In August, economist Dan Ariely, author of Predictably Irrational: The Hidden Forces That Shape Our Decisions, wrote about the "yoked dog" syndrome. In an experiment PETA surely disapproved of, two dogs received a series of mild shocks. One had a switch which turned off the shocks, and rapidly learned to use it. The other had no switch, though the other dog's switch turned off its shocks, too. At the end of the experiment, the second dog ended up whimpering in a corner.

In case you haven't figured it out, we are the yoked dog. Ariely warned that it would take just one more shock to send us over the edge. Instead, we've had a series of them — the disappearance of Wall Street, the reduction of Detroit's automakers to beggars, the largest job loss in decades.

And we've experienced these shocks not as complex stories, but as 140-character Twitter messages, emails, IMs, and Facebook status updates. The entrepreneurs behind Facebook, Digg, and Twitter have always styled their websites as the future of news, filtered by friends rather than editors. The result is that we have been constantly shocking ourselves. No one thinks to hit the "off" switch, even if we could find it.

Zuckerberg, more than anyone, has set his sights on having us share the entirety of our lives online. In a recent GQ profile, he wondered out loud about whether his site could capture our emotions in real time.

Is that really a good thing, to broadcast every passing mood to every casual acquaintance we connect with online? Behavioral economists like Ariely, who study the interplay of psychology with our economic decisions, have found that human beings are more motivated by fear of loss than hope of gain. And our biochemical evolution has set us up for fight-or-flight reactions to every flicker of shadow that crosses the savannah.

One can see how a real-time, computerized reporting system on other people's feelings can be helpful to, say, sufferers of Asperger's Syndrome, the autism-like condition that limits the ability to understand and react appropriately to emotion. But for the vast majority of us, who react like the yoked dog, the endless stream of data about just how bad things have gotten amounts to death by a thousand shocks.

Here's how Zuckerberg could do his part to save the world: An algorithm already rules what information shows up on our Facebook news feeds. By tweaking that to ban bad news and play up anything cheery, Zuckerberg could help us fight our urge to whimper in the corner. Otherwise, he's just leaving the world to go to the dogs.