With 22 books on spirituality and science, that have been translated in more than 25 countries, Ken Wilber (www.kenwilber.com, among others) is now the most translated writer on consciousness studies in the world. His debut The Spectrum of Consciousness (1977) established his reputation as an original thinker, who seeks to integrate Western and Eastern thought, and science and the world’s spiritual traditions. No Boundary (1979), which summarizes this work, is one of his most popular books. His core works The Atman Project (1980) and Up from Eden (1981) cover the territories of developmental psychology and cultural history respectively. In his recent work, especially the voluminous Sex, Ecology, Spirituality (1995), he has criticized not only Western culture, but also counter-cultural movements such as the New Age. In his opinion, none of these approach the depth and detailed nature of the "perennial philosophy", the conception of reality that lies at the heart of all major religions, and which forms the background of all his writings. This fundamental work has been summarized too, in A Brief History of Everything, one of his most widely read books.