An essential part of being human (and in fact of being a primate) is what psychologists call “theory of mind,” which is the ability to attribute mental states—beliefs, intentions, desires, plans, knowledge, thoughts, and so on—to others. When you have to give bad news to someone, for example, you know that they may become upset, and you take this into account in the way you talk to them. If you’re explaining something to another person you may anticipate certain questions they might ask. This is you employing a theory of mind.

This is such a basic part of our lives that we don’t give it a second thought, but that in itself can become a …