Symmetry is a fundamental principle of broad concern from the physical sciences to art and design. Much of its significance derives from the perceptual appeal of symmetry to the human brain, as testified by its universal inclusion in those icons of decor--oriental rugs. Although there have been many books on physical symmetry, none have addressed the issue of human symmetry perception. This comprehensive collection provides a wide range of approaches to the study of how we see symmetries, from evolutionary through empirical to extended theoretical treatments. The book is an invaluable resource for those concerned with the methods and analytic approaches to this challenging topic. It soon becomes evident that symmetry perception is not a simple example of neural pattern processing, since the essence of symmetry is to transcend the patterns of which it is composed. Consequently, this volume contains many novel methods relevant to the analysis of the long-range processing of mid-level vision rather than early neural filtering. It provides both a historical background and an intellectual stimulant to future developments in this lapidary field of study.