‘I got stones in my pathway/And my road seems dark at night/I have pains in my heart/They have taken my appetite’. Robert Johnson, known as the King of the Delta blues singers, distilled into these lines the essence of severe depressive illness – somatic ills, fear and suspicion, emotional and physical pain, nocturnal troubles and struggle against obstacles. The words are one with the powerful, haunting music. ICD-10 and DSM-IV have their place, but poets have often been there before us, and done a better job. We can all learn from Robert Johnson, born just 100 years ago.