Hearsay

To the heart and mind
Ignorance is kind
There's no comfort in the truth
Pain is all you'll find
--Wham

As demonstrated by this presidential election cycle, the number of people willing to engage in spreading and consuming hearsay is mind numbing. "Where there's smoke, there's fire" drives both producers and consumers of gossip.

As Goebbels understood, spreading false rumors is valuable because it works.

But it works only to the extent that people are willing to engage in the process. If they walk away, then the value of the rumor mill goes to zero.