The bottle cap hoax illustrates a phenomenon that may become more common as trust in old institutions like newspapers erodes and the power of propelling news - true and false - shifts to less formal networks of knowledge like the Internet and e-mail.
"Now," Adair says, "not only is that rumor making an end run around the media, it has a certain credibility because of who's sending it" - namely, the friends and relatives who pass along chain e-mails. In other words, you may not trust the St. Petersburg Times, but you still trust Uncle Al not to steer you wrong.
"Once these large institutions are not trusted, then rumors have much more power," says Nicholas DiFonzo, a professor of psychology at the Rochester Institute of Technology and the author of "The Water Cooler Effect."
"As people trust the press less and less, the public will be influenced by rumors more and more," he said.
We learned not to trust government.
Then we learned not to trust media.
We still trust Hollywood, because their propaganda pretends to be entertainment.
And we pretend to trust each other.