We’re living in an empirical age. The most impressive intellectual feats have been achieved by physicists and biologists, and these fields have established a distinctive model of credibility.

To be an authoritative figure, you want to be coolly scientific. You want to possess an arcane body of technical expertise. You want your mind to be a neutral instrument capable of processing complex quantifiable data.

The people in the human sciences have tried to piggyback on this authority model. For example, the American Psychiatric Association has just released the fifth edition of the Diagnostic Statistical Manual of Mental Health Disorders. It is the basic handbook of the field. It defines the known mental diseases. It creates stable standards, so that insurance companies can recognize various diagnoses and be comfortable with the medications prescribed to treat them.

The recent editions of this manual exude an impressive aura of scientific authority. They treat mental diseases like diseases of the heart and liver. They leave the impression that you should go to your psychiatrist because she has a vast body of technical knowledge that will allow her to solve your problems. With their austere neutrality, they leave a distinct impression: Psychiatrists are methodically treating symptoms, not people.