Founding of the Monist League Leads to the Eugenics Movement

Monism, a pantheistic philosophy that considered all things, animate and inanimate, as connected in some mystical way, was central to the philosophy of the biologist Ernst Haeckel. Members of the Monist League believed that the universe operated entirely by natural law and that human societies should strictly apply these laws. Although the Monist League was dissolved in 1933, the Nazis used the tenets of monist philosophy to justify racist and eugenic principles.

Summary of Event

Ernst Haeckel, a prominent biologist and proponent of Darwinism, believed that science was superior to religion as a source of understanding of nature and the human condition. He saw the study of nature as the highest form of intellectual endeavor and considered that all matter, both organic and inorganic, was infused with a unifying life force. His philosophy was based on monism, a pantheistic-like belief, and he considered Charles Darwin’s theory of natural selection to be scientific proof of monism’s truth. Monist League
Eugenics;Monist League
[kw]Founding of the Monist League Leads to the Eugenics Movement (Jan. 11, 1906)
[kw]Monist League Leads to the Eugenics Movement, Founding of the (Jan. 11, 1906)
[kw]Eugenics Movement, Founding of the Monist League Leads to the (Jan. 11, 1906)
Monist League
Eugenics;Monist League
[g]Germany;Jan. 11, 1906: Founding of the Monist League Leads to the Eugenics Movement[01570]
[c]Philosophy;Jan. 11, 1906: Founding of the Monist League Leads to the Eugenics Movement[01570]
[c]Organizations and institutions;Jan. 11, 1906: Founding of the Monist League Leads to the Eugenics Movement[01570]
Haeckel, Ernst
Hitler, Adolf
[p]Hitler, Adolf;eugenics
Ploetz, Alfred

Ernst Haeckel.

(Library of Congress)

Because humans are a part of nature, Haeckel believed that human society should operate by the laws of nature as he saw them. Haeckel viewed religion and nature as antithetical, and he suggested that religion be replaced with a more “primitive” religion of nature. Haeckelian monism stressed the struggle for existence based in nature and advocated applying Darwinian principles to society. Haeckel was convinced that the various human races were different species, some of which were superior to others. The Aryan race—especially the German race—was, he thought, the most advanced. Unfortunately, Haeckel said, intermarriage with other races and poor breeding practices had forced the Aryan race into decline. To remedy this issue, Haeckel determined that racial purity should be a German goal.

The egalitarian nature of democratic political systems was considered contrary to natural law. An autocratic and fascist-style government was seen as more natural, in that it theoretically allowed wise leaders to oversee society, which was viewed as a single body composed of individual citizens, much in the way that the human body is composed of individual cells. Just as different types of cells perform different functions in the body, each citizen’s inborn talents could be used to determine his or her assigned role in society. Women were seen as nurturers, and their primary role was to bear children and raise them to become productive members of society. As in nature, those individuals with more skilled or more important roles were given greater advantages.

Eugenics, a form of science focused on improving a given race, was a direct outgrowth of monism. In theory, application of eugenics to humans involves strengthening the population by selective breeding. Those with superior genetic traits would be encouraged to reproduce, and those with less desirable genetic traits could be discouraged, or even prevented, from reproducing. Awarding greater resources to those with more important roles in society, then, would encourage reproduction by genetically superior members of society. Haeckel even advocated such extreme approaches as sterilization of inferior individuals (such as the mentally ill or physically handicapped) and the euthanizing of infants born with serious defects. He even suggested that treating seriously ill individuals would be a waste of resources.

At the time the Monist League was founded, Haeckel was seventy-two years old. Although not active in the organization’s administration, he continued to give popular lectures on Darwinism and monism. After Haeckel’s death in 1919, the Monist League persisted until 1933, when it was disbanded. Its dissolution was not the result of philosophical differences between the organization and the Nazis or Nazi leader Adolf Hitler; clearly, Hitler incorporated many monist principles into Nazi philosophy. The heir to the Monist League was the Ernst Haeckel Association, or Ernst Haeckel Gesellschaft.

The Deutsche Gesellschaft für Rassenhygiene (German Society for Racial Hygiene) German Society for Racial Hygiene was established by Alfred Ploetz in Berlin in 1905. Like the Monist League, its philosophy centered on Aryan racial superiority and eugenics, and it was also a potent force in the development of Nazism and the National Socialist movement. As a physician, Ploetz actively advocated his so-called principles of racial hygiene and defended traditional notions of the German family. He was especially concerned about the “parasitic burden” of the degenerate and mentally ill and believed that such “impurities” needed to be cleansed from German society.

Although Haeckel was only able to propose eugenics as a way to improve the Aryan race, the Nazis and individuals like Ploetz were actually able to apply eugenics to the German population. The government gave certain physicians and geneticists permission to apply eugenic principles, and biometric data were gathered from the population to improve racial planning and to help support the contention that the Aryan race was superior to others. Interestingly, Hitler considered Jews to be relatively “fit” in a Darwinian sense: They had, after all, been able to survive centuries of harsh conditions. Their strength, however, only made their eradication more essential. According to Hitler’s Darwinian model, Aryans were in competition with Jews, and the superior race needed to apply the laws of nature to win.

Although eugenics was firmly rooted in monism and Darwinism, the form it took after the Nazis gained political power only partly incorporated these philosophies. The idea of the Aryan race’s superiority was difficult to reconcile with the monist contention that humans evolved from lower primates. Consequently, the purely naturalistic components of monism were largely minimized, except for eugenics, which was seen to have practical benefits for society. The Nazis believed that proper application of eugenics would propel the Aryan race toward complete domination over other races.


Haeckel’s Monist League was intended as the platform for dissemination of monist philosophy. Central to monist dogma was the belief that nature obeyed a single, unified law, the law of struggle for existence, as proposed by Darwin. Because humans were considered a part of nature, it was assumed that human society should operate by the laws of nature. Although Haeckel did not see the fruition of his ideas, later individuals—most notably Hitler—applied monist principles to Nazism. An integral part of the Nazi system was a belief in Aryan supremacy over other races and in eugenics as a way to purify the German race and improve it, and these ideas were lifted almost directly from Haeckelian monism. Monist League
Eugenics;Monist League

Further Reading

  • Gasman, Daniel. The Scientific Origins of National Socialism. Somerset, N.J.: Transaction, 2004. A thorough analysis of monism and its roots in nineteenth and early twentieth century Germany that shows its connection with Nazi eugenics programs.
  • Haeckel, Ernst. The Evolution of Man. 2 vols. 1879. Reprint. Whitefish, Mont.: Kessinger, 2004. Haeckel’s own theories about the origin of humankind and its relation to monism.
  • _______. Monism as Connecting Religion and Science. 1894. Reprint. Whitefish, Mont.: Kessinger, 2004. Based on a talk given by Haeckel at the seventy-fifth anniversary of the Naturforschende Gesellschaft des Osterlandes (Natural Research Society of the Eastern Region) in which he outlined the basic ideas of his monist philosophy.
  • Hau, Michael. The Cult of Health and Beauty in Germany: A Social History, 1890-1930. Chicago: University of Chicago Press, 2003. Deals with the German obsession with physical culture, which was at the root of German acceptance of the principles of eugenics.
  • Weindling, Paul. Health, Race, and German Politics Between National Unification and Nazism, 1870-1945. Cambridge, England: Cambridge University Press, 1993. A broad overview of the gradual changes in medicine and social programs in Germany that led to a comprehensive eugenics program as the Nazis consolidated their control of German politics.

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