Emeritus Professor of Ecumenical Theology at the University of Tübingen and president of the Foundation for a Global Ethic, he is one of the most important living philosophers of the twentieth century. He has been a priest since 1954 and, at the end of the 1970s, the Vatican rescinded his authority to teach Catholic Theology because of his critique of some aspects of official Church doctrine. Since 1995, he has been working full-time on the Global Ethic project, the subject of most of his more recent publications, for example Tracing the Way: Spiritual Dimensions of the World Religions (published in Spanish as En busca de nuestras huellas. La dimensión espiritual de las relaciones del mundo (Debolsillo, 2005)) and Global Responsibility: in Search of a New World Ethic, published in Spanish as Proyecto de una ética mundial (Trotta, 2006). He has recently published the first two volumes of his memoirs, My Struggle for Freedom: Memoirs (published in Spanish as Libertad Conquistada. Memorias by Trotta in 2003) and Disputed Truth, Memoirs Volume II (published in Spanish as Memorias, volumen II. Verdad controvertida, Trotta, 2009).