Chapter 4 begins with young ladies making wild guesses about Gatsby. He's a killer. He's second cousin to the devil. When we don't have information, we make assumptions. When we have a little information, we go way positive or way negative. If you don't believe me, have a look at online reviews. At one level, these schema (categories of thinking) can help us when we encounter new situations. However, when our inner ideas about people get loud enough to drown out the information right in front of us, they become ISMS (racism, sexism, ageism, etc.). Just look at how Fitzgerald describes Black and Jewish characters later in the chapter.