Play nice! How the internet is trying to design out toxic behaviour

Online abuse can be cruel - but for some tech companies it is an existential threat. Can giants such as Facebook use behavioural psychology and persuasive design to tame the trolls?

It was a book on the curious decline of the murder rate that gave Aja Bogdanoff her idea.

Her job back then stopped short of actual bloodshed, but it left her no stranger to the dark side of human nature. A software engineer who built and moderated online comment platforms, Bogdanoff spent her days wading through insults, and her spare time firefighting more urgent incidents. She could see platforms being overwhelmed by the sheer volume of antisocial users, but couldn't figure out how to get one jump ahead of them.