Our minds see and hear what our past experience has trained us to expect. Naturally, there are blanks in each individual experience, which is tied to our place of birth, family, schooling and the myriad of people who have influenced us in large or small ways. The mailman and the family dentist have caused us to think a certain way about all mailmen and dentists. My mailman and my dentist (each very competent at his job) don't represent all mailmen and dentists in the world; they're individuals. Generalizations about a group may contain accuracies, but they don't allow for individuality. If we look into the proverbial mirror, we may notice blanks in our experience, or blind spots, which can hinder us from seeing another person's point of view.
William M. Thackeray: Quotes: Reflection
"The world is a looking glass and gives back to every man the reflection of his own face."