Malcolm Gladwell’s Troublemakers extends his Blink thinking to how we generalize. The takeaway is “It doesn’t work to generalize about a relationship between a category and a trait when that relationship isn’t stable — or when the act of generalizing may itself change the basis of the generalization.”
In the article he asks whether pit bulls are dangerous dogs. It turns out they are only dangerous if bred, trained, or raised to be dangerous. A better indication of whether a dog may attack is if the dog displays aggressive behavior and has a negligent owner. Not an earth-shaking conclusion, but one we don’t always take the time to investigate.