Through four decades, public response to Ms. Sontag remained irreconcilably divided. She was described, variously, as explosive, anticlimactic, original, derivative, naïve, sophisticated, approachable, aloof, condescending, populist, puritanical, sybaritic, sincere, posturing, ascetic, voluptuary, right-wing, left-wing, profound, superficial, ardent, bloodless, dogmatic, ambivalent, lucid, inscrutable, visceral, reasoned, chilly, effusive, relevant, passé, ambivalent, tenacious, ecstatic, melancholic, humorous, humorless, deadpan, rhapsodic, cantankerous and clever. No one ever called her dull.