The boredom of everyday life

Is it possible for a writer to describe, as from the inside, an experience that he has never himself had? Can he, for example, describe what it is like to be delirious without ever having been delirious (and remembering it)? And if he does describe it, is his description worth anything; does it convey any real knowledge or insight to the reader?

Anton Chekhov (1860-1904), who was a doctor when delirium must have been much more common than it is today, describes both its exterior and interior, objectively and subjectively. In the story “The Teacher of Literature,” for example, Ippolit Ippolititch, a teacher of history and geography at a local school, dies of erysipelas of the face after a period of …