1724-1804 1842-1918 1865-1923 1884-1976 1886-1968 19thcentury 20thcentury barth bultmann cohen descriptionandtravel discoveryandexploration doctrinal ernst hermann herrmann history immanuel kant karl marburgschoolofphilosophy neo-kantianism philosophy religion robertbrewster rudolf stanton surveying theology troeltsch wilhelm