We aspire to a life without discomfort, without unpleasantness. But what kind of life would that be? It is as hard to imagine a world without pain as a person without sadness: a whole dimension of existence would be missing.

Last December, a Canadian pharmaceuticals executive and his wife were found strangled in their home. No one knows who did it or why, but everyone has a theory.

The events leading up to the botched execution of Clayton Lockett.

The placebo response doesn't care if the catalyst for healing is a triumph of pharmacology, a compassionate therapists, or a syringe of salt water. All it requires is a reasonable expectation of getting better.