Carl Gustav Carus (3 January 1789 – 28 July 1869) was a German physiologist and painter, born in Leipzig, who played various roles during the Romantic era. A friend of the writer Johann Wolfgang von Goethe, he was a many-sided man: a doctor, a naturalist, a scientist, a psychologist, and a landscape painter who studied under Caspar David Friedrich.
Carl Jung credited Carus with pointing to the unconscious as the essential basis of the psyche.
Although various philosophers, among them Leibniz, Kant, and Schelling, had already pointed very clearly to the problem of the dark side of the psyche, it was a physician who felt impelled, from his scientific and medical experience, to point to the unconscious as the essential basis of the psyche. This was C. G. Carus, the authority whom Eduard von Hartmann followed. (Jung [1959] 1969, par. 259)