Usually there are several possible responses to a question, which means you’re
traversing a tree. But essays are linear, not tree-shaped, which means you have
to choose one branch to follow at each point. How do you choose? Usually you
should follow whichever offers the greatest combination of generality and
novelty. I don’t consciously rank branches this way; I just follow whichever
seems most exciting; but generality and novelty are what make a branch exciting.
