When Sam Parker was researching his book about one of our most maligned emotions, time and time again, family, friends and colleagues would say the same thing: “I don’t really get angry”. It was, perhaps, an unsurprising response. Of all our emotions, anger has a singularly bad rep. The preserve of ranting politicians, faceless trolls and dustups on public transport that go viral. Little wonder the rest of us might want to distance ourselves from it.