One disease of working alone -the way writers mostly work- is dependence on mood. Mood is no measure and flips from highest to lowest in a millisecond ... Writers are bipolar by nature and by nature extreme.
— Donald Hall, Life Work
The essential point about the manic-depressive diagnosis, however, is that Greene accepted it—indeed, saw it as key to his personality and his work.
— Joan Acocella, “Graham Greene’s Dark Heart,” The New Yorker