During his talk, he elucidated some of his thoughts on how to write a novel. In at least one aspect his observations echoed those of Sebastian Junger last year -- he believes in writing what you don't know, and he enjoys challenging himself to write about things he didn't previously understand.
This is a not-quite-word-for-word-but-close transcription of what he said. English is not his first language, although he communicates comfortably in it: "There must be something about something that I don't know. Then I start to plan the story [until] I know what it is going to be about. Then I do the real, real structure. Most of the work is done before I [actually sit down to] write the book. People ask, 'Before you write, do you know how the story will end?' And I ask, 'On Friday night when you go out with your friends and you say "I have a story to tell you," do you know how that story will end? Of course you do!'"
He cited two main requirements for what he considers meaningful storytelling. First is an ability "to tell the story for someone else than yourself." Second, he believes "you have to have your own language," rather than imitating other writers or even sounding precisely like your speaking self. He didn't mention authorial "voice," however, and I was pleased because it's an over-used term that has become entangled in disparate ideas.
Mankell is fascinated with actual language -- words, foreign languages (he speaks and reads five, including fluency in Portuguese that rivals his native Swedish), printed pages, the meaning of religious texts, and more. The notion that he would prescribe "your own language" for a fiction writer makes sense given his world view (he lives half the year in Mozambique), in which he views global illiteracy rates as one of the greatest tragedies.
When he discussed global illiteracy earlier at a faculty lunch, he also told us what he considers the most important book in the world, and now I think I agree with him. It's the A-B-Cs.