But the crucial point about these productive outbursts – whether on the prehistoric savannah, or in the mundane domestic contexts of Averill’s research – is that there was an obvious route for translating anger into action, and thus reaching resolution. By contrast, we’ve built a world that’s extremely good at generating causes for anger, but extremely bad at giving us anything constructive to do with it. We live in denser settlements, and thus more frequently get each other’s backs up – but our gripes are usually with strangers, which means there’s no pre-existing relationship to discuss and recalibrate. (Your encounter with the jerk who barges past you on the train platform is likely to be the only time you ever meet him.)

We face big, systemic forces that threaten our wellbeing – automation, globalisation and above all climate change – but that offer few ways for individual people or communities to turn their anger into change. Incidentally, this also explains why “venting” your anger, by punching a pillow or suchlike, doesn’t work, and can even make things worse. That old advice is based on the assumption that emotions simply need release. But anger isn’t trapped wind. It doesn’t need somewhere to go. It needs something to do.

Social media, it almost doesn’t need saying, is where this problem reaches its extreme. The algorithms of the attention economy relentlessly expose us to enraging stories and opinions, for the straightforward reason that anger spreads more virally than other emotions – so you’re more likely to click, like, share and stay glued to Twitter or Facebook when you’re furious. Tabloid newspapers and Fox News figured this out years ago; but online, the diet of outrage can be customised precisely to include whatever drives you, personally, up the wall. It’s not so much that social media platforms are full of bigoted trolls and idiots with harebrained opinions, but rather that, however many there really are, the platforms are designed to ensure you can’t avoid the ones who infuriate you the most.