Human uses of mammals that "one is well advised to study the behaviour rather than attempting to get at any underlying emotion". Charles Darwin however had accepted the idea of emotion in animals, writing his 1872 book "The Expression of the Emotions in Man and Animals" on the subject. Darwin believed that mammals had social, mental and moral lives. In "The Descent of Man" (1871), he wrote: "There is no fundamental difference between man and the higher mammals in their mental faculties." Biologists remained wary of the idea, even for the great apes, but this led to serious difficulties, as Donald O. Hebb explained
Sociology of emotions actions that feed-back negatively on this self-destructive situation. The social management of emotions might be the fundamental dynamics of social cooperation and conflict around resources, complexity, conflict and moral life. It is well-established sociological fact that expression and feeling of the emotion of anger, for example, is strongly discouraged (repressed) in girls and women in many cultures, while fear is discouraged in boys and men. Some cultures and sub-cultures encourage or discourage happiness, sadness, jealousy, excitedness, and many other emotions. The free expression of the emotion of disgust is considered socially unacceptable in many countries. Sociologist Randall Collins has stated