Le Jia divided people into four colors: red, blue, yellow and green. Each color represents each personality, and then it is further analyzed. This book consists of two parts, the first part is the general introduction, and the second part is the specific rules. The general part mainly begins with a short story of squeezing toothpaste, so as to quickly judge which color it belongs to. At the same time, it answers the difference between personality color and people's common introversion or extroversion, rationality or sensibility. The specific part expounds how to deal with red, blue, yellow and green from the aspects of emotion, life, work, doing things and self-improvement. At the same time, it gives some personality analysis behind the orientation of outlook on life and values, such as what color people will buy houses and make investments based on what reasons and motives; What color is the last woman; What is the psychology behind people who don't get married?