This book provides a cross-cultural analysis of traditional social organization of the Old World Oikumene civilizations, which suggest that the world religions were its major determinant. The role of Christianity and Islam as determinants of social evolution is analyzed in more detail. Formal analysis performed in this book shows that though such factors as political centralization and class stratification were also important determinants, the difference in traditional social organization between Christian and Islamic cultures were mostly shaped by the respective world religions. This study also analyzes such topics as influence of Islam on social patterns in Sub-Saharan Africa and Southeast Asia, or Hinayana Buddhism influence on the evolution of kinship organization. This cross-cultural analysis makes it possible to provide an entirely new assessment of the old controversy between Materialism and Idealism, to move beyond both of these approaches.