June 2025 An essay has to tell people something they don't already know. But there are three different reasons people might not know something, and they yield three very different kinds of essays. One reason people won't know something is if it's not important to know. That doesn't mean it will make a bad essay. For example, you might write a good essay about a particular model of car. Readers would learn something from it. It would add to their picture of the world. For a handful of readers it might even spur some kind of epiphany. But unless this is a very unusual car it's not critical for everyone to know about it. [1] If something isn't important to know, there's no answer to the question of why people don't know it. Not knowing random facts is the default. But if you're going to write about things that are important to know, you have to ask why your readers don't already know them. Is it because they're smart but inexperienced, or because they're obtuse? So the three reasons readers might not already know what you tell them are (a) that it's not important, (b) that they're obtuse, or (c) that they're inexperienced. The reason I did this breakdown was to get at the following fact, which might have seemed controversial if I'd led with it, but should be obvious now. If you're writing for smart people about important things, you're writing for the young. Or more precisely, that's where you'll have the most effect. Whatever you say should also be at least somewhat novel to you, however old you are. It's not an essay otherwise, because an essay is something you write to figure something out. But whatever you figure out will presumably be more of a surprise to younger readers than it is to you. There's a continuum of surprise. At one extreme, something you read can change your whole way of thinking. The Selfish Gene did this to me. It was like suddenly seeing the other interpretation of an ambiguous image: you can treat genes rather than organisms as the protagonists, and evolution becomes easier to understand when you do. At the other extreme, writing merely puts into words something readers were already thinking — or thought they were. The impact of an essay is how much it changes readers' thinking multiplied by the importance of the topic. But it's hard to do well at both. It's hard to have big new ideas about important topics. So in practice there's a tradeoff: you can change readers' thinking a lot about moderately important things, or change it a little about very important ones. But with younger readers the tradeoff shifts. There's more room to change their thinking, so there's a bigger payoff for writing about important things. The tradeoff isn't a conscious one, at least not for me. It's more like a kind of gravitational field that writers work in. But every essayist works in it, whether they realize it or not. This seems obvious once you state it, but it took me a long time to understand. I knew I wanted to write for smart people about important topics. I noticed empirically that I seemed to be writing for the young. But it took me years to understand that the latter was an automatic consequence of the former. In fact I only really figured it out as I was writing this essay. Now that I know it, should I change anything? I don't think so. In fact seeing the shape of the field that writers work in has reminded me that I'm not optimizing for returns in it. I'm not trying to surprise readers of any particular age; I'm trying to surprise myself. The way I usually decide what to write about is by following curiosity. I notice something new and dig into it. It would probably be a mistake to change that. But seeing the shape of the essay field has set me thinking. What would surprise young readers? Which important things do people tend to learn late? Interesting question. I should think about that. Note [1] It's hard to write a really good essay about an unimportant topic, though, because a really good essayist will inevitably draw the topic into deeper waters. E. B. White could write an essay about how to boil potatoes that ended up being full of timeless wisdom. In which case, of course, it wouldn't really be about how to boil potatoes; that would just have been the starting point. Thanks to Jessica Livingston and Michael Nielsen for reading drafts of this.