When we encounter someone, usually the mind automatically slots the person into a category: man, woman, your friend Tom, the kid next door, etc. Watch this happen in your own mind as you meet or talk with a co-worker, salesclerk, or family member.

In effect, the mind summarizes and simplifies tons of details into a single thing – a human thing to be sure, but one with an umbrella label that makes it easy to know how to act. For example: “Oh, that’s my boss (or mother-in-law, or boyfriend, or traffic cop, or waiter) . . . and now I know what to do. Good.”

This labeling process is fast, …