color theory in the later decades of his life. He wrote several publications in the field, such as his Malerbriefe (Letters to a Painter, 1904) and Die Farbenfibel (The Color Primer, 1916). His work in color theory was influenced by that of Albert Henry Munsell, and in turn influenced Piet Mondrian and other members of De Stijl and Paul Klee and other members of the Bauhaus school. Ostwald's theories also influenced Americans Faber Birren and Egbert Jacobson. He was also interested in the international language movement, first learning Esperanto, then later supporting Ido. He was a member of a Committee of the Delegation for the Adoption of an International Auxiliary Language. Ostwald donated half the proceedings of his 1909 Nobel prize to the Ido movement, funding the Ido magazine Progreso which he had proposed in 1908. One of Ostwald's continuing interests was unification through systematization. In particular, Ostwald perceived that energy efficiency was a unifying theme in all facets of society and culture. In political matters, Ostwald's interest in energy efficiency extended to such political matters as the need for organization of labor. Ostwald's interest in unification through systematization led to his adaptation of the philosophy of Monism. Initially, Monism was liberal, pacifist, and international, seeking in science a basis of values to support social and political reforms. Ostwald himself developed a system of ethics based on science, around the core idea that one should "not waste energy, but convert it into its most useful form." in 1911, Ostwald became President of the Deutscher Monistenbund (Monist Association), founded by Ernst Haeckel. Ostwald (and other Monists) promoted eugenics and euthanasia, but only as voluntary choices with the intention of preventing suffering. Monist promotion of such ideas is suggested to have indirectly facilitated acceptance of the later Social Darwinism of the National Socialists. Ostwald died before the Nazis adopted and enforced the use of eugenics and euthanasia as involuntary government policies, to support their racist ideological positions. Ostwald's Monism also influenced Carl G. Jung's identification of psychological types. Honours and awards Ostwald received the 1909 Nobel Prize for Chemistry for his contributions to understanding catalysis and for his investigations of the fundamental principles underlying chemical equilibria and reaction rates. He was nominated for the Nobel Prize 20 times beginning in 1904, and he submitted nine nominations of other scientists for the Nobel Prize following his own award. This included two nominations of