An Explanation of Monism and Ethics (Letter to A.) C. T. Konstantin Eduardovich Tsiolkovsky is not just a philosophical treatise, but a deep reflection on the nature of man, his place in the universe and the ethical foundations that should guide our existence. This work, written by an outstanding Russian scientist and thinker, is an important milestone in the development of philosophical thought and ethics, and certainly deserves the attention of both science lovers and those interested in philosophy and moral issues. In his book, Tsiolkovsky seeks to explain the concept of monism - the idea of the unity of all things, that all phenomena and entities in the world are interconnected and are manifestations of the same reality. This philosophical doctrine finds a response in modern scientific research, where more and more scientists turn to ideas about the interconnectedness of all living and non-living things. Tsiolkovsky, as one of the founders of astronautics and theoretician, considers these issues from a unique point of view, which makes his reflections especially relevant in the context of today. The book will be of interest to a wide range of readers - from undergraduate and graduate students studying philosophy and ethics, to those who just want to understand more deeply how monism can affect our perception of the world and moral decisions. Tsiolkovsky addresses eternal questions: what is the nature of good and evil? What are our responsibilities to ourselves and others? How can we coexist harmoniously in this complex world? These topics concern people of all ages and professions, and the book offers fascinating reflections on these important issues. Tsiolkovsky's style, as always, is distinguished by clarity and depth. His ability to communicate complex ideas in a simple and accessible language makes his work attractive to a wide audience. In the "Explanation to Monism and Ethics" the reader will be able to see how the author masterfully combines scientific facts and philosophical reflections, creating a holistic and harmonious work. It's not just reading - it's a journey into the world of ideas, where everyone will find something important and personal. The book also raises questions about the future of humanity, about how scientific advances can affect ethical norms and values. Tsiolkovsky, a pioneer in space exploration, wonders how expanding the horizons of our existence could change our understanding of morality and responsibility. In this context, his reflections become particularly relevant, given the current challenges facing humanity. “An Explanation of Monism and Ethics” is not just a philosophical work, but a real storehouse of ideas that can change our perception of the world and ourselves. This book will be an excellent addition to the library of anyone interested in ethics, philosophy and science. It inspires reflection and encourages the search for answers to the most important questions that concern humanity for centuries. If you are looking for a work that combines deep philosophy, scientific ideas and practical reflections on life, then Konstantin Tsiolkovsky’s “Clarification to Monism and Ethics” is exactly what you need. Allow yourself to immerse yourself in this world of ideas and discover new horizons of understanding.