He was periodically paralyzed by self-reproach and insecurity, and once wrote a defensive third-person preface to one of his later novels (The Age of Longing) in which he described its style as modeled on that of a certain “A. Koestler,” whose writing, “lacking in ornament and distinction, is easy to imitate.” The author himself was written off as “a much afflicted scribe of his time, greedy for pleasure, haunted by guilt, who enjoyed a short vogue and was then forgotten, like the rest of them.”
[. . .]
Otto Katz once said to him, “We all have inferiority complexes of various sizes, but yours isn’t a complex—it’s a cathedral.” Koestler liked this remark so much that he included it in his autobiography, thus attaining the status of one who could actually brag about his inferiority complex as if size mattered.