I had “a strong suspicion that I’d done my best work and anything more would be inferior. I was by this time no longer in possession of the mental vitality or the verbal energy or the physical fitness needed to mount and sustain a large creative attack of any duration on a complex structure as demanding as a novel…. Every talent has its terms — its nature, its scope, its force; also its term, a tenure, a life span…. Not everyone can be fruitful forever.”