On June 4, the satirical news site the Science Post published a block of "lorem ipsum" text under a frightening headline: "Study: 70% of Facebook users only read the headline of science stories before commenting."

Nearly 46,000 people shared the post, some of them quite earnestly — an inadvertent example, perhaps, of life imitating comedy.

Now, as if it needed further proof, the satirical headline's been validated once again: According to a new study by computer scientists at Columbia University and the French National Institute, 59 percent of links shared on social media have never actually been clicked: In other words, most people appear to retweet news without ever reading it.

Worse, the study finds that these sort of blind peer-to-peer shares are really important in determining what news gets circulated and what just fades off the public radar. So your thoughtless retweets, and those of your friends, are actually shaping our shared political and cultural agendas.