This book explores the constitutive role alterity plays in identity formation in Western and Eastern traditions. It examines the significance of difference in conceptions of identity across major philosophical and religious traditions in a global and comparative context, considering Ancient Greek and Egyptian, Chinese, Islamic, European and Japanese philosophies. In addition, the book opens up discussion of less dominant trends in philosophical thinking, particularly the spaces between self-same existence and otherness in the histories of philosophical and religious thought. Chapters critique both essentialist and postmodern understandings of self-constitution by questioning the ordinary narrative of identity construction across Western and non-Western traditions. The book also explores the construction of selfhood from a wide range of perspectives, drawing upon individual philosophers (including Plotinus, Descartes, Geulincx, Hume, de Beauvoir and Ueda) as well as religious and philosophical movements, including Confucian philosophy, Zen Buddhism, Protestantism and Post-Phenomenology. Differences in Identity in Philosophy and Religion represents a landmark study, drawing together a range of approaches, perspectives and traditions to explore how identity is constructed across the world.