After this had been going on for about one year, I finally asked him, “Why always an hour and a half?” He answered, “That’s easy. I have found out that my attention span is about an hour and a half. If I work on any one topic longer than this, I begin to repeat myself. At the same time, I have learned that nothing of importance can really be tackled in much less time. One does not get to the point where one understands what one is talking about.”
