Corollary: the more general the ideas you’re talking about, the less you should worry about repeating yourself. If you write enough, it’s inevitable you will. Your brain is much the same from year to year and so are the stimuli that hit it. I feel slightly bad when I find I’ve said something close to what I’ve said before, as if I were plagiarizing myself. But rationally one shouldn’t. You won’t say something exactly the same way the second time, and that variation increases the chance you’ll get that tiny but critical delta of novelty.

And of course, ideas beget ideas. (That sounds familiar.) An idea with a small amount of novelty could lead to one with more. But only if you keep going. So it’s doubly important not to let yourself be discouraged by people who say there’s not much new about something you’ve discovered. “Not much new” is a real achievement when you’re talking about the most general ideas.

It’s not true that there’s nothing new under the sun. There are some domains where there’s almost nothing new. But there’s a big difference between nothing and almost nothing, when it’s multiplied by the area under the sun.