Except, perhaps for rule five, all of those seem applicable to nonfiction. Though the measures for "talent" are rather different between the two. In the case of

Except, perhaps for rule five, all of those seem applicable to nonfiction. Though the measures for "talent" are rather different between the two. In the case of seven, "Write to be informative" might suffice, in the sense that your greatest purpose is to have the reader come away from your having absorbed as much of the material successfully as possible. Though with that said, most of the best nonfiction books I've read, even textbooks, had the occasional traces of humor and other lightheartedness.