People are incredibly rude to each other on social media. Much ruder than they would ever be face to face. The great potential of the internet to bring humanity together in a glorious collaborating network seems naïve – instead of embracing a massive extension of our social circles, we seem to revert to tribalism and conflict online. And while we generally conduct our real-life interactions with strangers with politeness and respect, online, we can be horrible.

But it was our human ability to communicate ideas across networks of people that enabled us to so successfully solve life’s challenges and to build the modern world. Gaia Vince travels to Yale University to meet the researchers who are studying how we cooperate today and why it can go wrong when we communicate online.

Part of the Crossing Divides season.

(Photo: Row of children hugging Credit: Kieferpix/Getty Images)