In 1989, a trainee physician called Edward Bullmore treated a woman in her late fifties. Mrs P had swollen joints in her hands and knees. She had an autoimmune disease. Her own immune system had attacked her, flooding her joints with inflammation. This, in turn, had eaten away at Mrs P’s collagen and bone, noted Bullmore, who was 29, and whose real ambition was to become a psychiatrist.

He asked Mrs P some routine questions about her physical symptoms, and made a correct diagnosis of rheumatoid arthritis. Then he asked her a few questions he wasn’t supposed to ask. How was she feeling? How would she describe her mood? Well, said Mrs P, she was feeling very low – she was tired, listless and losing