This reading comes from the Facing History and Ourselves resource Race and Membership in American History: The Eugenics Movement.

In the mid-1700s, a few European thinkers tried to apply the ideas and methods of science to humans and human societies. These thinkers were part of a movement known as the “Enlightenment.” Although they disagreed on a number of points, most came to believe that all humans everywhere have the ability to reason and form societies. In time, those theories shaped the way ordinary people viewed the world. If societies are human inventions, some argued, people may alter or even replace an oppressive government with one more to their liking. In 1776, thirteen colonies along the eastern coast of North America broke their ties to Britain. 

Thomas Jefferson of Virginia wrote their Declaration of Independence. It states:

We hold these truths to be self-evident: That all men are created equal; that they are endowed by their Creator with certain inalienable rights; that among these are life, liberty, and the pursuit of happiness. That, to secure these rights, governments are instituted among men, deriving their just powers from the consent of the governed; that, whenever any form of government becomes destructive of these ends, it is the right of the people to alter or abolish it, and to institute a new government, laying its foundation on such principles, and organizing its powers in such form, as to them shall seem most likely to effect their safety and happiness.

The French Revolution was also inspired by the ideals of the Enlightenment. In 1789, in their Declaration of the Rights of Man and Citizen, the French boldly stated that “Men are born, and always continue, free and equal in respect of their rights.” As a French leader explained, “Since men are all made of the same clay, there should be no distinction or superiority among them.” He and other thinkers of the Enlightenment regarded human differences as differences in degree rather than in kind.

Although the great thinkers of the Enlightenment stressed the equality of humankind, the notion that humanity is divided into separate but unequal races developed during those same years. Historian Londa Schiebinger offers one explanation:

The expansive mood of the Enlightenment—the feeling that all men are by nature equal—gave middle- and lower-class men, women, Jews, Africans, and West Indians living in Europe reason to believe that they, too, might begin to share the privileges heretofore reserved for elite European men. Optimism rested in part on the ambiguities inherent in the word “man” as used in revolutionary documents of the period. The 1789 [French] Declaration of the Rights of Man and Citizen said nothing about race or sex, leading many to assume that the liberties it proclaimed would hold universally. The future president of the French National Assembly, Honoré-Gabriel Riqueti, comte de Mirabeau, declared that no one could claim that “white men are born and remain free, black men are born and remain slaves.” Nor did the universal and celebrated “man” seem to exclude women. Addressing the Convention in 1793, an anonymous woman declared: “Citizen legislators, you have given men a constitution . . . as the constitution is based on the rights of man, we now demand the full exercise of those rights for ourselves.”

Within this revolutionary republican framework, an appeal to natural rights could be countered only by proof of natural inequalities. The marquis de Condorcet wrote, for instance, that if women were to be excluded . . . one must demonstrate a “natural difference” between men and women to legitimate that exclusion. In other words, if social inequalities were to be justified within the framework of Enlightenment thought, scientific evidence would have to show that human nature is not uniform, but differs according to age, race, and sex.

Scientific communities responded to this challenge with intense scrutiny of human bodies, generating countless examples of radical misreadings of the human body that scholars have described as scientific racism and scientific sexism. These two movements shared many key features. Both regarded women and non-European men as deviations from the European male norm. Both deployed new methods to measure and discuss difference. Both sought natural foundations to justify social inequalities between the sexes and races.1

  1. Citations

    • 1 Nature’s Body: Gender in the Making of Science by Londa Schiebinger. Copyright ©1993 by Londa Schiebinger. Reprinted by permission of Beacon Press, Boston, pp. 143-145.

Connection Questions

  1. What does the idea of equality mean to you? Does the idea that “all men are created equal” imply that there are no differences? To what extent have Americans achieved equality? To what extent does it remain a dream? What is the power of that dream? How does that dream relate to citizenship?
  2. Londa Schiebinger regards the development of scientific racism and sexism at a time when the great thinkers of the Enlightenment were stressing the equality of humankind as a paradox. How does she account for contradictions? How do you account for them?
  3. According to Schiebinger, the thinkers of the Enlightenment encouraged a search for “evidence . . . that human nature is not uniform, but differs according to age, race, and sex.” What does she suggest inspired that search? What consequences might such a search have? Suppose the Enlightenment had sought evidence of the similarities among humankind. What might have been the consequences of that search for society? For individuals within that society?  

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