Heard Mentality

When somebody hears something and believes it to be fact even though it is just hearsay, and splits off into a new herd of sheeple.

Susan whispers to the new secretary Gina, "Here comes Jimmy. Don't give him any attention because he has 'Heard Mentality' and will go on and on if he thinks you believe him."
Jimmy "Hi Gina I'm Jimmy. Say, have you heard about the ____(conspiracy_of_the_day)____? This video is evidence it's true. You have to watch the whole thing though and they splain it all!. It's only 59 minutes long."