- Kierkegaard, Søren, 1813-1855 (13)
- Feuerbach, Ludwig, 1804-1872 (12)
- Hirsch, Emanuel (8)
- Bolin, Wilhelm, 1835-1924 (5)
- Jodl, Friedrich (5)
- Hegel, Georg Wilhelm Friedrich, 1770-1831 (4)
- Gerdes, Hayo (2)
- Sass, Hans-Martin, 1935- (2)
- Bolin, Wilhelm (1)
- Eucken, Rudolf Christof, 1846-1926 (1)
- Frauenstädt, Julius (1)
- Junghans, Hans Martin (1)
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