In some ways, the distinction between normalcy and pathology is arbitrarily defined—as well as hard to measure.

As Virginia Woolf testified in On Being Ill, “English, which can express the thoughts of Hamlet and the tragedy of Lear, has no words for the shiver and the headache. . . . The merest schoolgirl, when she falls in love, has Shakespeare or Keats to speak her mind for her; but let a sufferer try to describe a pain in his head to a doctor and language