To be convincing and to be persuasive are two different goals in essay-writing. A convincing essay telegraphs the writer’s authority, whether via deep research or rigorous thought. A persuasive essay, on the other hand, simply communicates “here's why I should win this argument.”

In the American school system, students are most commonly taught how to write a persuasive essay–AKA one based on the essay’s archaic form as a kind of legal argument. But the essay as a tool for thought works best when it is inquisitive rather than argumentative, following a line of thought all the way through to its logical end.

This means that where an essay takes you will often be a surprise, whether you are writing it or reading it. Paul Graham says:

The trick is to use yourself as a proxy for the reader. You should only write about things you've thought about a lot. And anything you come across that surprises you, who've thought about the topic a lot, will probably surprise most readers.