The distinction between positive and negative eugenics is perhaps the best-known distinction that has been made between forms that eugenics takes. Roughly, positive eugenics refers to efforts aimed at increasing desirable traits, while negative eugenics refers to efforts aimed at decreasing undesirable traits. Still, it is easy to fall into confusion in drawing and deploying the distinction in particular contexts. Clarity here is important not only historically, but also for appeals to the distinction in contemporary discussions of “new eugenics” or “newgenics”.

Positive vs Negative Eugenics: The Basic Distinction
The basic idea behind the distinction is relatively easy to convey. Eugenics aims to use science for human improvement over generations by changing the composition of human populations; it does so by favouring the reproduction of certain sorts or kinds of people over others. That favouring could take the form of facilitating the reproduction of some—those with desirable traits—or it could take the form of inhibiting the reproduction of others—those with undesirable traits. The first of these is positive eugenics; the second is negative eugenics.

Historically, positive eugenic measures have included promoting the idea that healthy, high-achieving people should have children, or have larger families; introducing institutions and policies that encourage marriage and family life for such people; and establishing sperm banks where eugenically desirable traits, such as intelligence, are criterial either for donors or are listed as present in the donor for users to consider in their choices. Negative eugenic measures have included immigration restriction based on putatively eugenically undesirable traits, including race, nationality, and ethnicity; discouragement or prohibition of marriage and family life for those with eugenically undesirable traits; and sexual segregation, sterilization, and euthanasia of those with such traits.

Origins of the Distinction
Even before coining the term “eugenics” in 1883, Sir Francis Galton had focused his eugenic gaze on the putative heritability of desirable traits, like intelligence and good character, in his book Hereditary Genius (1869). Around that same time, eugenic ideas in North America that arose through the eugenic family studies, beginning with Richard Dugdale's The Jukes (1877), were focused on undesirable traits, such as pauperism, insanity, and alcoholism.

The obstetrician Caleb Williams Saleeby originally drew the distinction between positive and negative eugenics at the beginning of Part II of his Parenthood and Race Culture: An Outline of Eugenics (1909), where he turns from the theory to the practice of eugenics. However, Saleeby here says of these two forms of eugenics, simply that the “one would seek to encourage the parenthood of the worthy, the other to discourage the parenthood of the unworthy” (p.172), noting that positive and negative eugenics are complementary and manifestations of the very same principle. As is made clear earlier in the book, Saleeby sees himself as following Galton's lead in a number of ways. First, Saleeby sees negative eugenics as being of increasing importance as a practical measure, and in light of this, goes on to articulate the sorts of people who fall under the heading of the “eugenically unworthy”. As Saleeby lists them, these are the deaf and dumb, the feeble-minded, the insane (including the “epileptic insane”), and the criminal. Second, with the appeal to “encourage” and “discourage”, there is an emphasis on the role of education in both positive and negative eugenics, particularly with respect to parenting ability and heredity, which Saleeby himself considers to be distinct aspects of the eugenic worthiness and unworthiness of individuals.

These two points elucidate several broader features of early 20th-century eugenics. This first shows that it was not simply people with certain traits who were subject to eugenic measures, but certain sorts of people. Each of the sorts of people that Saleeby lists is taken by Saleeby to pick out people in virtue of a hereditary trait. But Saleeby himself makes clear in his extension of positive and negative eugenic measures to cases beyond these that the distinction applies to “worthy” and “unworthy” traits more generally. The second illustrates that the distinction between positive and negative eugenics is orthogonal to questions of state sanctions, compulsoriness, and reproductive autonomy. Thus, even negative eugenic goals do not require, and in fact may be more readily achieved through, educative, quasi-voluntary, or even voluntary means.

Eugenics, Newgenics, and Limits of the Distinction
Historically, positive eugenics has seemed to many to be a more acceptable form of eugenics than negative eugenics. This is in part because of the apparent direct connection between positive eugenics and the goals of human improvement and public health, in part because of an association with choice, consent, and non-coercion, and in part because of the drastic forms that negative eugenics has taken, particularly in Nazi sterilization and euthanasia programs.

By contrast, in that part of contemporary bioethics concerned with the selection of and against certain kinds of fetuses, it is positive eugenics that has seemed to pose deeper moral problems. This stems from the fact that in bioethics it is largely taken for granted that eliminating “diseased” or “deformed” fetuses is morally unproblematic, whereas parental choice regarding what “worthy traits” one's offspring have is to dabble in “playing God”, selecting “designer babies”, or engaging in some kind of transhumanism. Moreover, negative eugenic measures to eliminate undesirable traits in fetuses through selective abortion are seen as a kind of treatment, while positive eugenic measures to choose desirable traits in offspring are viewed as a kind of enhancement. Although disability sensitive critics of selective abortion, such as Adrienne Asch (2000, 2003) and Marsha Saxton (2003) have challenged mainstream bioethics here, the locus of ethical debate over "newgenics" has not shifted (e.g., Sparrow 2013).

Worth keeping in mind here is that positive and negative eugenics often travel hand-in-hand. In cases in which a eugenic policy imposes a strict requirement or constraint, this follows logically: to require that someone have a given trait to reproduce, for example, implies that only those with that trait, and no one without that trait, can reproduce. Artificial or natural selection for a trait in a given population is also selection against the absence of that trait in the population. For example, in selecting for having the genetic make-up to produce blue eyes, one is also selecting against having non-blue eyes (e.g., brown or green eyes).

Less demanding positive eugenic policies or practices that are differentially implemented, however, will also be at least implicitly negatively eugenic in their effects (and vice-versa). For example, actively encouraging immigration from certain countries as part of a eugenic policy (positive eugenics) is likely to discourage immigration from other countries; conversely, requiring that immigrants meet certain health requirements (negative eugenics) is likely to facilitate the immigration of those with the “worthy” traits associated with those health requirements.

-Robert A. Wilson

• Asch, Adrienne. (2000). Why I haven’t changed my mind about prenatal diagnosis: Reflections and reminders. In Erik Parens and Adrienne Asch (eds.) Prenatal Testing and Disability Rights (pp. 234-258). Georgetown.

• Asch, Adrienne (2003). Disability equality and prenatal testing: Contradictory or compatible? Florida State University Law Review 30, 315-342.

• Galton, Francis (1869). Hereditary genius. London: Macmillan.

• Rodwell, Grant. (1997). Dr. Caleb Williams Saleeby: The complete eugenicist. History of Education 26, 23-40.

• Saleeby, Caleb Williams (1909). Parenthood and race culture: An outline of eugenics. New York: Moffat, Yard, and Co.

• Saxton, Marsha. (2000). Why members of the disability community oppose prenatal diagnoses and selective abortion. In Erik Parens and Adrienne Asch (eds.) Prenatal Testing and Disability Rights (pp. 147-164). Georgetown.

• Sparrow, Robert. (2013, April 4). In vitro eugenics. Journal of Medical Ethics. doi:10.1136/medethics-2012-101200

• Wilkinson, Stephen. (2010). On the distinction between positive and negative eugenics. In Matti Häyry, Tuija Takala, Peter Herissone-Kelly and Gardar Árnason (eds.), Arguments and Analysis in Bioethics (pp.115-127). Amsterdam: Rodopi.