The Latin word "placebo" means "I shall please." The word occurs in the Latin translation of Psalm 116: "I shall please the dead in the land of the living." In the Middle Ages, hired mourners chanted this line in the Vespers for the Dead. Because the mourners were hired, their sorrow was insincere, and people therefore called them "placebos." The word was first used in the context of medicine in the eighteenth century, when it was applied to medicines that were in a sense "insincere" because they pretended to cure without any known medicinal properties.
Throughout the history of medicine, placebos or "pleasers" have always played a part in cures. Just by having faith in a pill or poultice, even if they had no pharmacological properties, a patient could often get relief from his suffering. As Voltaire once said, "The art of medicine consists in amusing the patient while nature cures the disease." So persistent has the effect of placebos been in history, that this year Harvard University has opened an institute at Beth Israel Deaconess Medical Center in Boston to study in depth how placebos work.
Although modern medicine is primarily a science, those who are interested in placebo research believe, as Voltaire did, that medicine is also an art. And it is the art of medicine, they believe, the complex interaction between doctor and patient, that may have a curative property over and above what can be accomplished by scientifically based pharmacological cures.
I have found this to be true in my own experience. Last month, I suffered from a painful chest cough. Finally, I went to my doctor. After examining me and listening attentively to my account of my symptoms, he prescribed an antibiotic. As I walked out of the doctor's office, on my way to fill the prescription, I noticed that I was already feeling better. Not only were my spirits higher, but I wasn't coughing as much. Simply the expectation that the antibiotics would help me--something I had experienced in my previous bouts of bronchitis--was making me feel noticeably better, even before I had taken a single capsule. To me, this was a vivid example of how my mind could affect physical symptoms in my body.
Therapeutic hypnosis, of course, relies on the healing power of expectation and suggestion, and this is part of what current researchers are calling the placebo effect. As Michael Specter points out in a recent New Yorker article called "The Power of Nothing," current placebo research indicates that it is not merely drugs or surgery that help the patient. The very interaction between the doctor and patient may have a healing property of its own. The very expectation that the doctor will cure him may stimulate endorphins in the patient's brain and make him feel better before he has taken the drugs or undergone the surgery. Specter makes a distinction between disease and illness. Although pharmaceutical drugs may heal the patient's disease, the art of medicine may play a larger part in healing the patient's illness than we previously believed.
Psychotherapy is an art not a science. Of course, in forging the diverse tools in our therapy toolbox, we rely on a large collection of empirical knowledge and outcome studies. From the experience of our mentors we know which techniques work best with which problems. We use one strategy that has worked in the past to help symptoms of anxiety and another that has worked for PTSD. We use certain techniques to help clients with phobias and other techniques to help clients with depression. But the most rigorous of recent outcome studies indicate that, at the end of the day, it is the quality of the therapist-patient relationship that is the primary curative factor in psychotherapy. At least in part, psychotherapy's effectiveness seems to reside in the placebo effect.