"I have often wondered for what good end the sensations of Grief could be intended."

-- Thomas Jefferson

Thomas Jefferson suffered during his life from periodic bouts of dejection and despair, shadowed intervals during which he was full of "gloomy forebodings" about what lay ahead.

Not long before he composed the Declaration of Independence, the young Jefferson lay for six weeks in idleness and ill health at Monticello, paralyzed by a mysterious "malady." Similar lapses were to recur during anxious periods in his life, often accompanied by violent headaches. In Jefferson's...