Ernst Marcus (philosopher)

Ernst Moses Marcus (3 September 1856, Kamen – 30 October 1928, Essen) was a German lawyer and philosopher. He developed a theory of aether based on Immanuel Kant's posthumous work Opus Postumum, however sharply disagreeing with Erich Adickes' interpretation. He used this to mount a criticism of Albert Einstein's theory of relativity.^[1] He was a major influence on Salomo Friedlaender.

Ernst was the son of Robert Ruben Marcus and Berta Marcus.^[2] He studied law in Bonn and Berlin. Whilst working as an Assessor in 1889 he developed an interest in philosophy. In 1890 he was appointed as a judge in Essen. In 1893 he married Berta Auerbach, with whom he had three children.^[3]

In 1899 he started regular meetings with Salomo Friedlaender, who admired his theses and became a firm supporter of him. Friedlaender referred to him by the epithet "the Krupp of logic".