- Jaspers, Karl, 1883-1969 (4)
- Dilthey, Wilhelm, 1833-1911 (2)
- Nietzsche, Friedrich Wilhelm, 1844-1900 (2)
- Baeumler, Alfred, 1887-1968 (1)
- Baillie, J. B. (James Black), Sir, 1872-1940 (1)
- Becker, Oskar, 1889-1964 (1)
- Cohn, Jonas, 1869-1947 (1)
- Geiger, M. (1)
- Hegel, Georg Wilhelm Friedrich, 1770-1831 (1)
- Husserl, Edmund, 1859-1938 (1)
- Jaspers, Ludger (1)