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Richard Pillard

Richard Pillard is an American psychiatrist known for work on biology and sexual orientation. Some of Pillard’s research covered the trans community.

Pillard considered a process of “defeminization” to be a central concept in a model of gender transposition developed with James Weinrich. It contains elements of John Money’s neurodevelopmental model. [2]

Pillard also made the unfortunate decision to work with transphobic psychologist J. Michael Bailey for some research.


Richard Colestock Pillard was born 11 October 1933 in Springfield, Ohio. Pillard briefly attended Swarthmore College before transferring to Antioch College, where father Basil H. Pillard was an English Professor. [3] Pillard earned a bachelor’s degree from Antioch followed by a medical degree from University of Rochester, with a internship at Boston City Hospital. [4]

Pillard married Vassar graduate Cornelia Livingston Cromwell in 1958, while in medical school. They later divorced, and Pillard now identifies as gay. Pillard has three children. The oldest, Vicky Pillard, is a pediatrician. Middle child Nina Pillard is a Georgetown University Law Center professor and was formerly assistant to Attorney General Janet Reno. Youngest child Eliza Pillard is a social worker specializing in child psychiatric issues in Vermont.

Trans research

Pillard held an appointment at the Boston University School of Medicine.

Pillard says that it had long puzzled him why transsexuals—men or women who wish to live in bodies of the opposite sex—are so different from gay people: “You’d think they’d be on the far end of the spectrum, the ‘gayest of the gay.'” And yet transsexuals are not in fact gay. Whereas gay men, quite comfortably and unalterably, see themselves as men, male transsexuals see themselves as women trapped in men’s bodies. Pillard and a colleague, James Weinrich, a psychobiologist at the University of California at San Diego, began to theorize that gay men are men who in the womb went through only a partial form of sexual and psychosexual differentiation. More precisely, Pillard and Weinrich theorized that although gay men do undergo masculinization—they are, after all, fully male physically—they go incompletely if at all through another part of the process: defeminization.[1]

Chandler Burr reported that Pillard jokes “he is uniquely equipped to investigate whether homosexuality has a biological basis: he, his brother, and his sister are gay, and Pillard believes that his father may have been gay. One of Pillard’s three daughters from a marriage early in life is bisexual. This family history seems to invite a biological explanation, and it made Pillard start thinking about the origins of sexual orientation.” [1]

Heritability of sexual orientation

Pillard is well-known for a series of studies coauthored with J. Michael Bailey, which examined the rate of concordance of sexual identity among monozygotic twins, dizygotic twins of the same sex, non-twin siblings of the same sex, and adoptive siblings of the same sex. In all studies they found rates of concordance variantly consistent with the hypothesis that homosexuality has a significant genetic component. The Council for Responsible Genetics and other researchers have criticized this work for using a self-selected sample, a problem which later studies have attempted to remedy.

Pillard feels that some of his most significant work deals with the incidence of homosexuality running in families.

Model of trans people

Aaron Devor summarized Pillard this:

Richard Pillard & James Weinrich attempted to incorporate much of this range of biological research into a comprehensive theory of gender transpositions. Their theory was largely a biological one in which they shared many of Money’s assumptions about developmental determinism functioning within a framework of nature / critical period / nurture. Pillard and Weinrich’s model of gender transpositions is appealing in its comprehensiveness. It has been both highly praised and sorely criticized for overgeneralizing from the data on which it was built and excessively stretching to reach conclusions from inconclusive evidence.

These theorists built their model on two biological processes which they argued were formative of gender, sex, and sexuality. They started by pointing out that all human development begins by proceeding in a female direction. The author then argued that in order for human embryos to develop into males they must both be defeminized and masculinized. They were conceived of as separate processes which normally happen in several stages at different points in the development process and at different times for different parts of the body. Thus, they argued, a malfunction or mistiming of either or both of these processes would result in either an intersexed condition of the body or a gender transposition of the mind / brain. Although they credited both hormonal and socialization influences for defeminization and masculinization, their arguments focused most closely on pre- or perinatal hormonal controls on gender and sexual development. They further argued that it was only after puberty that gendered behaviours become two-dimensional wherein one might be either / or, neither / nor, or both masculine and feminine.

 Hillard and wine Rich proposed that the best way to understand the full range of human gendered and sexual behaviours and identities is to visualize a four-part grid with degrees of masculinization forming one axis and degrees of defeminization forming the other axis. Thus normal normative heterosexual women and most male-to-female transsexuals would inhabit the corner of the grid representing both the least masculinized and the least defeminized people, whereas normative heterosexual men and most female-to-male transsexual would occupy the corner of the array representing both the most masculinized and the most defeminized people.

In the portion of their grid denoting defeminized but on masculinized Persons, they placed some male-to-female transsexuals; certain males who because of insensitivity to androgens look, feel, and act like women; and some lesbian women. They did so because, Pillard and Weinrich argued, All of these people exhibit low levels of the characteristics of both masculinity and femininity. In the corner representing people who had been masculinized but undefeminized, they placed most gay men and many lesbian women who, they argued, exhibit some combination of both fairly well developed masculinity and femininity.

Pillard and Weinrich concluded that “sexual orientation is the result of a complex developmental process … with antecedents and not rigid determinants in … biobehavioral masculinization and defeminization” and that “in humans (and most primates as well), masculinization has become, through heterochrony, somewhat or greatly decoupled from defeminization. This decoupling process provides evolution the opportunity to produce human beings with novel combinations of masculinization and defeminization.” It is through these mechanisms they argued that female-to-male transsexuals are made.

Devor (1997)


* Pillard RC, Rose RM, Sherwood M. Plasma testosterone levels in homosexual men. Arch Sex Behav. 1974 Sep;3(5):453-8. PMID 4415098

* Pillard RC, Weinrich JD (1987). The periodic table model of gender transpositions, part 1: a theory based on masculinization and defeminization of the brain. The Journal of Sex Research Vol. 23, No. 4, pp. 425-454.

* Bailey JM, Pillard RC. A genetic study of male sexual orientation. Arch Gen Psychiatry. 1991 Dec;48(12):1089-96. PMID 1845227

* Tuttle GE, Pillard RC. Sexual orientation and cognitive abilities. Arch Sex Behav. 1991 Jun;20(3):307-18. PMID 2059149

* Pillard RC, Weinrich JD. Evidence of familial nature of male homosexuality. Arch Gen Psychiatry. 1986 Aug;43(8):808-12. PMID 3729676

* Pillard RC, Poumadere J, Carretta RA. A family study of sexual orientation. Arch Sex Behav. 1982 Dec;11(6):511-20. PMID 6760832

* Pillard RC, Poumadere J, Carretta RA. Is homosexuality familial? A review, some data, and a suggestion. Arch Sex Behav. 1981 Oct;10(5):465-75. PMID 7032464

* Dawood K, Pillard RC, Horvath C, Revelle W, Bailey JM. Familial aspects of male homosexuality. Arch Sex Behav. 2000 Apr;29(2):155-63. PMID 10842723

* Bailey JM, Pillard RC, Dawood K, Miller MB, Farrer LA, Trivedi S, Murphy RL. A family history study of male sexual orientation using three independent samples. Behav Genet. 1999 Mar;29(2):79-86. PMID 10405456

* Pillard RC, Bailey JM. Human sexual orientation has a heritable component. Hum Biol. 1998 Apr;70(2):347-65. PMID 9549243

* Pillard RC, Bailey JM. A biologic perspective on sexual orientation. Psychiatr Clin North Am. 1995 Mar;18(1):71-84. PMID 7761309

* Snyder PJ, Weinrich JD, Pillard RC. Personality and lipid level differences associated with homosexual and bisexual identity in men. Arch Sex Behav. 1994 Aug;23(4):433-51. PMID 7993184

* Pillard RC, Rosen LR, Meyer-Bahlburg H, Weinrich JD, Feldman JF, Gruen R, Ehrhardt AA. Psychopathology and social functioning in men prenatally exposed to diethylstilbestrol (DES). Psychosom Med. 1993 Nov-Dec;55(6):485-91. PMID 8310108

* Weinrich JD, Snyder PJ, Pillard RC, Grant I, Jacobson DL, Robinson SR, McCutchan JA. A factor analysis of the Klein sexual orientation grid in two disparate samples. Arch Sex Behav. 1993 Apr;22(2):157-68. PMID 8476335

* Bailey JM, Pillard RC, Neale MC, Agyei Y. Heritable factors influence sexual orientation in women. Arch Gen Psychiatry. 1993 Mar;50(3):217-23. PMID 8439243


1. Burr, Chandler (June 1997). Homosexuality and biology: the puzzles of chemistryThe Atlantic

2. Devor, AH (1997). FTM: Female-to-Male Transsexuals in Society. Indiana University Press 9780253212597

3. Judson, Jerome (March 1958). Departure: Basil Pillard, 1895-1957. College English, Vol. 19, No. 6, Poetry and Professors Issue, p. 240.

4. Paul E. Lynch (2003). An Interview with Richard C. Pillard, MD. Journal of Gay & Lesbian Psychotherapy Volume: 7, Issue 4, 63-70.


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