The book "What Social Classes Owe Each Other" by William Graham Sumner is one of the classic works in sociology that examines the relationship between social classes. The author analyzes the concept of responsibility and duties of different classes in society, examining the moral aspects of this issue. In the book, Sumner highlights the problem of social justice, equality and solidarity, inviting the reader to discuss the moral obligations of social classes to each other. This work makes you think about the difference in property status and opportunities of people of different social strata, as well as how it affects society as a whole. "What social classes owe to each other" is an important book not only for sociologists and philosophers, but also for all those interested in problems of social justice and morality. Her text remains relevant today, reminding us of the importance of understanding and interaction between different social classes.