How does Mr. Eco manage to find time to do so many things all at once?

During the interview, Mukund Padmanabhan reiterates David Lodge’s surprise on Umberto Eco’s large amount of works and how he manages to write them all. To this Eco replies that just like the universe has empty spaces, our lives too, have a lot of empty spaces; he calls them ‘interstices’. Whenever he has a few moments to spare in between two different tasks, instead of wasting them, he uses the time to write. He even gives an example of his working technique. He says that while waiting for someone to come up the elevator he keeps himself busy.