Thus, concepts aren’t fixed definitions in your brain, and they’re not prototypes of the most typical or frequent instances. Instead, your brain has many instances—of cars, of dot patterns, of sadness, or anything else—and it imposes similarities between them, in the moment, according to your goal in a given situation. For example, your usual goal for a vehicle is to use it for transportation, so if an object meets that goal for you, then it’s a vehicle, whether it’s a car, a helicopter, or a sheet of plywood with four wheels nailed on.
