Nature versus Nurture:

The Impact of the Case of David Reimer on Current Psychology

Chelsea deBruijn
Camosun College



Where does the field of psychology stand on the nature versus nurture debate? When considered, this question can be broken down into the nature theory, which stresses that human behavioral and physical traits are determined by innate qualities and the nurture theory, which emphasizes that these traits are structured through socialization and learning. It seems as though the quest to determine the relative importance of nature and nurture, in relation to psychological phenomena, is no closer to being settled today than it was at any point in the past (Bors, 1994). However, a number of cases have shaken the foundation upon which the nature versus nurture controversy was built, providing new understandings. One such case, that of David Reimer, is of particular significance. When the decision was made for Reimer to undergo gender reassignment surgery, in 1966 (David Reimer, 2004), it was unlikely that any of the parties involved could have imagined the repercussions that would follow. By examining the ideological circumstances under which Reimer’s situation occurred, as well as the outcome, one can begin to grasp the influence that ensued. The case of David Reimer and subsequent research by John Money and Milton Diamond, contributed a large information base for the ongoing nature versus nurture debate in current psychology.


            The life of David Reimer began in a Winnipeg hospital, in the summer of 1965, when Janet Reimer gave birth to twin boys, Bruce (who would later become David) and Brian (David Reimer, 2004). Within six months both boys encountered difficulty urinating and their doctors suggested that they be circumcised. The doctors chose to use an unconventional method of circumcision and botched the surgery, burning Bruce’s penis beyond the point of surgical reparation. The Reimers were then told that Bruce would have to live out the rest of his life without a penis (Hyde et al., 2006). One night the Reimers came across a television program that showcased an American, Dr. John Money, and his theories on sex and gender (David Reimer, 2004). Dr. John Money was a professor of pediatrics and medical psychology at the John Hopkins University in Baltimore .He believed strongly in a developing theory, the social learning theory, which was gaining popularity at the time. (Holden, 1988).


            The social learning theory gained prevalence during the 1960’s, a decade which transformed the field of psychology, by means of a major paradigm shift. During the early 1960’s, mounting evidence suggested that the traditional psychodynamic practices, in use at the time, lacked both therapeutic and predictive power. It was at this point that a Canadian professor, Albert Bandura, and his students at Stanford University, created a powerful treatment, which was a vehicle for change. Their theory of human behavior brought about new modes of treatment, analytic methodologies, and conceptual models. It focused on the idea that people were not only products of their life circumstances, but producers of them as well, with the power to effect changes by actions. Bandura’s social learning theory lent itself readily to social applications (Gold medal awarded, 2006), and for this reason it is not surprising that John Money embraced it and applied it to his own theories on sex and gender.


Money felt that gender was determined by how a child was raised, rather than by his or her biology, a basic element of the social learning theory (Hyde et al., 2006). He felt that it was nurture, not nature that determined a child’s gender and that, if caught early enough boys could be raised as girls (David Reimer, 2004). Individuals could be successfully assigned to either gender, Money argued, providing that the necessary surgeries and hormone treatments be administered and that the assignment take place in infancy. He claimed that these beliefs were backed up by his research on intersex individuals (Hyde et al., 2006). In his theories, Money also seemed to ascribe to the standard beliefs used in sex assignment that, according to Milton Diamond (1997), “were so strongly held by pediatricians that they could be considered medical postulates” (p. 200). These standard assumptions were that: the sex of a child should not be changed after two years of age; the appearance of one’s genitals determines healthy psychosexual development; at birth individuals are psychosexually neutral; and doubt should not be allowed, concerning the sex of assignment (Diamond, 1997). 


Based on his knowledge, experience and the influences of the time, Money suggested to the Reimers, who had since contacted him, that Bruce would live a happy and healthy life if he were raised as a female. Because Bruce and Brian were twins who shared not only genes, but family and intrauterine environments as well, they were considered valid subjects for further exploring the social learning concept of gender identity. The Reimers decided to take Money’s advice and at the age of 21 months, Bruce’s testicles were removed. What remained of his penis was left in place, so as not to interfere with his urinary tract (David Reimer, 2004). David was reported as being the first case of reassignment/reconstruction on an unambiguous XY male, who was born without abnormalities concerning sexual differentiation (David Reimer: Encyclopedia, 2007).


From the time that Bruce was released from the hospital, the Reimers raised him as a girl. They followed the counsel of Dr. Money and resolved not to tell him the truth (Hyde et al., 2006). Bruce was renamed Brenda and Janet Reimer did her best to raise him as a girl; she dressed him up in skirts and taught him how to use makeup. However, the transformation did not go smoothly (David Reimer, 2004). Brenda did not really fit in as a girl, she preferred stereotypical male play (Hyde et al., 2006) and was often made fun of by the children for her male mannerisms, being called names such as “caveman”, “freak” and “it”. Brenda reported feeling increasingly lonely and no longer wanted to attend school. When Brenda reached the age of nine, the Reimers began having serious doubts about their decision (David Reimer, 2004). 


On the other hand, Dr. John Money felt that the transformation was a success. He published an article arguing this point in the Archives of sexual behavior, at which time the case became widely known as the John/Joan case. Money stated that “The child’s behavior is so clearly that of an active little girl and so different from the boyish ways of her twin brother” (David Reimer, 2004). He claimed that the case reinforced the idea of gender as a social construct. Brian, Bruce’s twin brother, remembered things differently though. He felt that the only difference between he and Brenda was that Brenda had longer hair. By the time that Brenda reached puberty she had begun to develop a thick neck and thick shoulders, at which time it became clear that the experiment was not going according to the plan that Money had laid out. It was around the same time that Money had begun to pressure the Reimers to take the final step, and have surgery to construct a vagina for Brenda (David Reimer, 2004).


Brenda rebelled about the surgery; she threatened to commit suicide if she was forced to visit Dr. Money again (David Reimer, 2004). Mr. and Mrs. Reimer then decided to tell her the truth about everything. While Brenda was shocked, she was also somewhat relieved, later saying “Suddenly it all made sense why I felt the way I did” (Hyde et al., 2006, p. 122). Within months of learning the truth, Brenda changed his name to David, cut his hair, began wearing masculine clothing and underwent a number of surgeries to give him a more masculine body. While David was much happier with his reclaimed gender, he still struggled with depression. He felt that he might never find an accepting partner (Hyde et al., 2006), and attempted suicide three times, the third leaving him in a coma. When David finally recovered he began the path towards leading a normal life (David Reimer, 2004). He met and married a woman named Jane and fathered their three children. Despite all of these accomplishments, David still battled  depression, especially following the death of his twin brother. David committed suicide on May 4th, 2004, at the age of 38 (Hyde et al., 2006).


The story of David Reimer has had a profound impact on the way in which western society views gender identity. In 2000, John Colapinto wrote As Nature Made Him: The Boy Who was Raised as a Girl, which was followed by a frenzy of media exposure across Canada and the United States. It was around this time that The John Hopkins Children’s Centre released two studies, which concluded that the sex of male babies is determined as a result of exposure to prenatal male hormones (David Reimer, 2004), thus supporting the idea that hormones have a strong influence on brain differentiation and gender identity. The Centre stated that the current practice of sex-reassignment, in some of the infants, was seriously being questioned (David Reimer, 2004).


Following the revelations surrounding the outcome of David Reimer’s case, the reputation of John Money was damaged and his theory about gender plasticity was discounted. Money has since gone on to conduct further research and provide further insight into the complicated nature versus nurture controversy regarding gender identity. In The Future of Sex and Gender (1980), Money wrote that there is no backtracking in human beings, as in mammals, once sex differentiation of the fetus has taken place. He further stated that a clitoris will not turn into a penis, regardless of androgen treatment and that a penis cannot be induced to shrink and turn into a clitoris. It seems as though Money had begun to see gender identity as more than just a result of social learning, and was beginning to credit a connection between genetics and gender. Others in the field were also drawing similar inferences.


A professor of anatomy and reproductive biology at the University of Hawaii, named Milton Diamond, published a paper in the Journal of Sex Research in 1997. He claimed that an individual is born with prenatal biases that affect how he or she will interact with the world, despite older theories which claimed the contrary. He discussed the case of David Reimer and linked David’s feelings of being malassigned to the idea that he likely observed and compared himself with his peers and from there became critical of his own gender. Diamond argued that behavioral differences occur in children at such an early age, that they must be inherent, and have little to do with the appearance of one’s genitals. He then went further and declared gender identity as being distinct from sexual identity (Diamond, 1997).


 For David Reimer, and a number of other individuals in similar situations, Diamond felt that solidifying their sexual identity was vital to their existence and the securing of their inner persona. He also stated that gender identity develops prior to, or along with, the recognition of preferred gender patterns. Sexual orientation and sexual identity, which are social phenomena distinct from gender identity, develop later. As a result of these theories, Diamond argued that the traditional pediatric postulates, concerning sex assignment/reassignment, were in need of an adjustment. Sex assignment protocols, in which one set of rules are applied to every situation, were not valid, he claimed. According to Diamond, society needed to come to terms with different genital conditions and realize that not everyone fits into a distinct male or female category. For future cases in which sex reassignment is a consideration, Diamond suggested that no decisions be made until the child is of age to participate in the decision making process and that both the child and caregivers be compassionately informed, with long term evaluation and guidance provided (Diamond, 1997).


Diamond then presented a new set of postulates, which are as follows: any doubt as to gender, identity or orientation should be openly discussed; at birth, individuals are psychosexually biased; whenever the decision is made by informed choice, change of sex should be supported; and while psychosexual development is related to the appearance of genitals, it is not dependent upon it. Diamond stressed the idea that while these are recommendations, no simple set of rules are appropriate in all conditions. The ideas expressed by Diamond mirror those of Aristotle, concerning the theory that in medical treatment, perfection cannot be demanded. Over 2000 years ago, Aristotle theorized that while happiness is the ultimate goal, the way in which it is attained can be debatable (Diamond, 1997).


 Concerning ethics, Aristotle proclaimed that  “Precision (in ethics) cannot be expected…The problem of the good, too presents a similar kind of irregularity, because in many cases good things bring harmful results…Search (instead) for that degree of precision in each kind of study which the nature of the subject at hand admits” (Diamond, 1997, p. 211). According to this philosophy, the parameters surrounding ethics are not always clear. Mistakes can be made in the medical field, even though, in many cases, those committing them are only striving for the best results, to produce the greatest good.  These mistakes ultimately lead to a better understanding for future application. However, what is considered to be the most ethical manner in approaching a given situation is subject to change.


The case of David Reimer solidifies these ideas of change surrounding ethics. Prior to David’s case, it was felt that the social learning theory could be applied in the case of gender reassignment, which concerned unambiguous XY male infants. Because of this belief, Dr. John Money suggested that David undergo gender reassignment surgery and be raised as a female (David Reimer, 2004). However, when David rebelled against his newly assigned gender, a number of individuals in the field of psychology began to question this decision. Milton Diamond, for example, claimed that the application of the social learning theory was inadequate in gender reassignment, as behavioral differences in children are inherent and have little to do with the appearance of their genitals. Diamond then went further and made suggestions for future cases, going so far as to rewrite the traditional pediatric medical postulates (Diamond, 1997). Though the case of David Reimer and subsequent research have not put the nature versus nurture controversy to rest, they have helped to lay a solid foundation upon which current psychology can continue to progress.




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