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This might be the reason Facebook doesn’t have a dislike button.

The social network has been conducting secret experiments on us.

Really.

What sounds like something from a work of fiction is something real you can read in a paper in the Proceedings of the National Academy of Sciences, which explains how and why Facebook used nearly 700,000 news feeds and manipulated them in the name of research to study “emotional contagion through social networks.”

To read and comment on this story, go here.

Facebook founder and CEO Mark Zuckerberg
Jim Watson / AFP/Getty Images / Sept. 18, 2013

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