No mental illness has, or ever will be, diagnosed on the basis of medical signs, for a simple reason. If people who have been diagnosed with schizophrenia are found to have a brain lesion, they are suffering from a brain illness, not a mental illness. The presence of a medical sign in people who have been labelled mentally ill proves that they are not suffering from a mental illness. Psychiatry is, therefore, that branch of medicine where diagnoses of ‘illnesses’ are made in the absence of objective evidence: they are based, not on what people have, but on what they do and say. And if they act in ways that annoy, upset or offend others, they may find themselves diagnosed as mentally ill and treated medically against their will.