A philosophical analysis of human nature is given: his finitude, abandonment, anxiety, fear of death, sociality, uncertainty, metaphysicality, transcendence, rationality, etc. Modifications of the general nature of man are associated with the historical development of society. The naked man, formed by collectivist civilizations, is contrasted with the alienated man, generated by individualistic civilizations. Nudity acts as an integral characteristic expressing the essential similarity of thoughts, feelings and actions of the “cogs” of one smoothly working social machine realizing its global goal. A common feature that speaks of people’s isolation from each other and from society as a whole, of deep, painfully experienced differences in thoughts, feelings and actions, is alienation. The final part of the book is devoted to “the loving person,” an explanation and understanding of human behavior, and the modern threat of destruction of human nature.