“What I think is true is that at a certain stage in his life he deliberately ceased to take any interest in himself except as a kind of spiritual alumnus taking his moral finals...Self-knowledge for him had come to mean recognition of his own weakness and shortcomings and nothing more. Anything beyond that he sharply suspected, both in himself and in others, as a symptom of spiritual megalomania. At best, there was so much else, in letters and in life, that he found much more interesting! As far as I am able to judge, it was this that lay behind that distinctive combination of an almost supreme intellectual and 'phantastic' maturity, laced with moral energy, on the one hand, with...a certain psychic or spiritual immaturity on the other”
Book:Light on C. S. Lewis