When I was a child, someone was only mad if they thought they were Napoleon or a teapot, and everyone else was 'normal'. Thankfully, things are a little more nuanced now, but how far from 'normal' do you have to get before you have a 'condition'? The answer seems to be: not very far at all. The latest edition of Diagnostic and Statistical Manual of Mental Disorders (DSM) was published last month. It lists mental disorders and symptoms, and every edition is fatter than the last. Why is there this boom in new disorders?