Immanuel Kant's "Metaphysical Foundations of Ethics" is a fundamental philosophical work that reveals the basic principles of morality. In this book, the author considers the concepts of moral obligations, responsibility and freedom in the context of human activity. Kant argues that the basis of moral laws is the very nature of a rational being, not external circumstances or the consequences of actions. His interpretation of ethical issues is of great importance for the development of moral philosophy and is one of the best examples of classical ethical thought.