The book by the famous German economist and philosopher, leader of the German socialist movement Karl Kautsky (1854–1938) examines the problems of ethics and their connection with the materialist understanding of history. The study has been conducted since the time of Plato, when the ethical nature of man first became the subject of consideration by philosophers, and until the 19th century, when historical materialism, in the author’s opinion, deprived the moral ideal of its significance as a guiding fact in social development. The book is of interest to both specialists - historians and philosophers , political scientists, and for a wide range of readers.The text of the book was translated from the original language using an artificial intelligence program. For the most part, the translation of the text is of very high quality, but in some cases, due to the imperfection of the technology, there may be incorrect phrase translations in the text, as well as single words and expressions may not be translated.