Why humans evolved into such good bullshitters ( www.vox.com )

A psychologist explains our obsession with other people’s opinions.

Roughly 6 million years ago, our chimpanzee ancestors migrated from the dense rainforest to the open savannah in East Africa. It was one of the most significant events in the history of human evolution.

Life on the sprawling grasslands precipitated a shift from individualistic ways of living to more cooperative ways. This was the birth of what you might call “social intelligence,” and it changed the way our minds work forever.

It explains why our psychological health depends so heavily on our status within a particular social group. It even explains why we love to exaggerate and why we’re so good at believing each other’s bullshit.

This is the argument psychology professor William von Hippel makes in his fascinating new book The Social Leap. According to Hippel, the move from the rainforest to the savannah produced a cascade of advances in human intelligence and innovation that led inexorably to the world we live in today. But it also cemented pathologies in the human mind that continue to shape how we live, think, and judge.

I spoke with Hippel about the significance of the “social leap” and why he believes this mostly overlooked part of human history explains so many of our psychological quirks.

A lightly edited transcript of our conversation follows.

Sean Illing

Your book is obviously about the past, but it has just as much to say about the present, about why human beings are so strange and self-destructive. Why tell this story now?

William von Hippel

I’m really interested in social intelligence. I want to know what makes people socially successful. And I’ve