George Lindbeck (b. 1923) is a Lutheran theologian and known today as an advocate of postliberalism. However, "for most of his career he was known primarily as a medievalist and, above all, as a theologian at the forefront of ecumenical dialogue." Lindbeck has a BA from Gustavus (1943) and a BD and PhD from Yale University (1946; 1955). While still finishing his doctoral degree, Lindbeck was appointed to the Yale faculty in 1952 where he remained until his retirement in 1993. He is well known for his Cultural-Linguistic approach to doctrine which he argues in his book, The Nature of Doctrine (1984). Hans Frei, Paul Holmer and David Kelsey have had a major influence on his thought.